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2.5. Xác định cấu tạo peptit qua phản ứng thủy phân

Peptit X có công thức cấu tạo Gly-Ala-Gly-Glu có số liên kết peptit là 

Hóa học Lớp 12
Xem chi tiết 8 K lượt xem 6 năm trước
20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.    A rainbow is an optical display of color that usually appears in the sky when a beam of sunlight refracts through millions of raindrops. Each (31) ______ color from the spectrum is then sent to your eyes. For this to happen, the angle between the ray of light, the raindrop and the human eye must be between 40 and 42 degrees.    After studying rainbows in (32) ______, Sir Isaac Newton was able to explain how they are formed. However, he was color blind, so he had to rely on the eyes of his assistant, who could easily (33) ______ all the seven colors: red, orange, yellow, green, blue, indigo and violet. His assistant could also clearly tell the difference between indigo and violet.    There are two types of rainbows. Primary rainbows are the most common and have the most distinctive colors, with red appearing on the outside of the arc and violet on the inside. Secondary rainbows are unusual because the light is reflected twice within the raindrop before it (34) ______ a rainbow, so the colors are in reverse order and not as bright as primary rainbows.    There is a popular myth that if you reach the end of a rainbow, you will find a pot of gold waiting for you. In fact, it is impossible to do this, because a rainbow has no end - as you go towards the point where the rainbow seems to touch the ground, it moves away from you as quickly as you (35) ______.Điền ô số 35

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 613 lượt xem 6 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.What is “extreme” weather? Why are people talking about it these days? “Extreme” weather is an unusual weather event such as rainfall, a drought or a heat wave in the wrong place or at the wrong time. In theory, they are very rare. But these days, our TV screens are constantly showing such extreme weather events. Take just three news stories from 2010: 28 centimetres of rain fell on Rio de Janeiro in 24 hours, Nashville, USA, had 33 centimetres of rain in two days and there was record rainfall in Pakistan.The effects of this kind of rainfall are dramatic and lethal. In Rio de Janeiro, landslides followed, burying hundreds of people. In Pakistan, the floods affected 20 million people. Meanwhile, other parts of the world suffer devastating droughts. Australia, Russia and East Africa have been hit in the last ten years. And then there are unexpected heat waves, such as in 2003 in Europe. That summer, 35,000 deaths were said to be heat-related.So, what is happening to our weather? Are these extreme events part of a natural cycle? Or are they caused by human activity and its effects on the Earth’s climate? Peter Miller says it’s probably a mixture of both of these things. On the one hand, the most important influences on weather events are natural cycles in the climate. Two of the most famous weather cycles, El Niño and La Niña, originate in the Pacific Ocean. The heat from the warm ocean rises high into the atmosphere and affects weather all around the world. On the other hand, the temperature of the Earth’s oceans is slowly but steadily going up. And this is a result of human activity. We are producing greenhouse gases that trap heat in the Earth’s atmosphere. This heat warms up the atmosphere, land and oceans. Warmer oceans produce more water vapour – think of heating a pan of water in your kitchen. Turn up the heat, it produces steam more quickly. Satellite data tells us that the water vapour in the atmosphere has gone up by four percent in 25 years. This warm, wet air turns into the rain, storms, hurricanes and typhoons that we are increasingly experiencing. Climate scientist, Michael Oppenheimer, says that we need to face the reality of climate change. And we also need to act now to save lives and money in the future.Extreme weather can be caused by ______.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1 K lượt xem 6 năm trước
Bài 8: Điện năng. Công suất điện.

Dẫn một đường dây điện sợi đôi từ mạng điện chung tới một ngôi nhà cách đó L = 20 m. Biết mỗi sợi dây đơn có một lõi đồng với thiết diện bằng 0,5mm2 với điện trở suất của đồng là 1,8.10-8Ωm. Hiệu điện thế ở cuối đường dây, ngay tại lối vào nhà là 220 V. Trong nhà sử dụng các đèn dây tóc nóng sáng với tổng công suất 330 W trung bình 5 giờ mỗi ngày. Nhiệt lượng tỏa ra trên đường dây dẫn trong vòng 30 ngày xấp xỉ bằng

Vật lý Lớp 11
Xem chi tiết 25.8 K lượt xem 6 năm trước
Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 15)

Amino axit X no, mạch hở có công thức phân tử CmHnO4N. Mối quan hệ giữa n với m là

Hóa học Tốt nghiệp THPT
Xem chi tiết 267 lượt xem 6 năm trước
20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.    A rainbow is an optical display of color that usually appears in the sky when a beam of sunlight refracts through millions of raindrops. Each (31) ______ color from the spectrum is then sent to your eyes. For this to happen, the angle between the ray of light, the raindrop and the human eye must be between 40 and 42 degrees.    After studying rainbows in (32) ______, Sir Isaac Newton was able to explain how they are formed. However, he was color blind, so he had to rely on the eyes of his assistant, who could easily (33) ______ all the seven colors: red, orange, yellow, green, blue, indigo and violet. His assistant could also clearly tell the difference between indigo and violet.    There are two types of rainbows. Primary rainbows are the most common and have the most distinctive colors, with red appearing on the outside of the arc and violet on the inside. Secondary rainbows are unusual because the light is reflected twice within the raindrop before it (34) ______ a rainbow, so the colors are in reverse order and not as bright as primary rainbows.    There is a popular myth that if you reach the end of a rainbow, you will find a pot of gold waiting for you. In fact, it is impossible to do this, because a rainbow has no end - as you go towards the point where the rainbow seems to touch the ground, it moves away from you as quickly as you (35) ______.Điền ô số 34

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 292 lượt xem 6 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.What is “extreme” weather? Why are people talking about it these days? “Extreme” weather is an unusual weather event such as rainfall, a drought or a heat wave in the wrong place or at the wrong time. In theory, they are very rare. But these days, our TV screens are constantly showing such extreme weather events. Take just three news stories from 2010: 28 centimetres of rain fell on Rio de Janeiro in 24 hours, Nashville, USA, had 33 centimetres of rain in two days and there was record rainfall in Pakistan.The effects of this kind of rainfall are dramatic and lethal. In Rio de Janeiro, landslides followed, burying hundreds of people. In Pakistan, the floods affected 20 million people. Meanwhile, other parts of the world suffer devastating droughts. Australia, Russia and East Africa have been hit in the last ten years. And then there are unexpected heat waves, such as in 2003 in Europe. That summer, 35,000 deaths were said to be heat-related.So, what is happening to our weather? Are these extreme events part of a natural cycle? Or are they caused by human activity and its effects on the Earth’s climate? Peter Miller says it’s probably a mixture of both of these things. On the one hand, the most important influences on weather events are natural cycles in the climate. Two of the most famous weather cycles, El Niño and La Niña, originate in the Pacific Ocean. The heat from the warm ocean rises high into the atmosphere and affects weather all around the world. On the other hand, the temperature of the Earth’s oceans is slowly but steadily going up. And this is a result of human activity. We are producing greenhouse gases that trap heat in the Earth’s atmosphere. This heat warms up the atmosphere, land and oceans. Warmer oceans produce more water vapour – think of heating a pan of water in your kitchen. Turn up the heat, it produces steam more quickly. Satellite data tells us that the water vapour in the atmosphere has gone up by four percent in 25 years. This warm, wet air turns into the rain, storms, hurricanes and typhoons that we are increasingly experiencing. Climate scientist, Michael Oppenheimer, says that we need to face the reality of climate change. And we also need to act now to save lives and money in the future.The word -that in the third paragraph refers to ______.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 665 lượt xem 6 năm trước
Tổng hợp đề thi thử THPTQG môn Vật lí năm 2020 cực hay có lời giải (Đề số 5)

Tại mặt nước có hai nguồn sóng kết hợp S1, S2 cách nhau 12 cm, dao động đồng pha nhau với tần số 20 Hz. Điểm M cách S1, S2 lần lượt 4,2 cm và 9 cm. Biết tốc độ truyền sóng trên mặt nước là 32 cm/s. Để M thuộc vân cực tiểu thì phải dịch chuyển S2 theo phương S1S2 ra xa S1 một khoảng tối thiểu bằng

Vật lý Tốt nghiệp THPT
Xem chi tiết 438 lượt xem 6 năm trước
20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.    A rainbow is an optical display of color that usually appears in the sky when a beam of sunlight refracts through millions of raindrops. Each (31) ______ color from the spectrum is then sent to your eyes. For this to happen, the angle between the ray of light, the raindrop and the human eye must be between 40 and 42 degrees.    After studying rainbows in (32) ______, Sir Isaac Newton was able to explain how they are formed. However, he was color blind, so he had to rely on the eyes of his assistant, who could easily (33) ______ all the seven colors: red, orange, yellow, green, blue, indigo and violet. His assistant could also clearly tell the difference between indigo and violet.    There are two types of rainbows. Primary rainbows are the most common and have the most distinctive colors, with red appearing on the outside of the arc and violet on the inside. Secondary rainbows are unusual because the light is reflected twice within the raindrop before it (34) ______ a rainbow, so the colors are in reverse order and not as bright as primary rainbows.    There is a popular myth that if you reach the end of a rainbow, you will find a pot of gold waiting for you. In fact, it is impossible to do this, because a rainbow has no end - as you go towards the point where the rainbow seems to touch the ground, it moves away from you as quickly as you (35) ______.Điền ô số 33

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 413 lượt xem 6 năm trước
Chương V. CHẤT KHÍ

Biết khối lượng của 1 mol nước là  m=18.10-3kg và 1 mol có NA=6,02.1023 phân tử. Biết khối lượng riêng của nước là  m=103 kg/m3. Số phân tử có trong 300 cm3 là

Vật lý Lớp 10
Xem chi tiết 16.6 K lượt xem 6 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.What is “extreme” weather? Why are people talking about it these days? “Extreme” weather is an unusual weather event such as rainfall, a drought or a heat wave in the wrong place or at the wrong time. In theory, they are very rare. But these days, our TV screens are constantly showing such extreme weather events. Take just three news stories from 2010: 28 centimetres of rain fell on Rio de Janeiro in 24 hours, Nashville, USA, had 33 centimetres of rain in two days and there was record rainfall in Pakistan.The effects of this kind of rainfall are dramatic and lethal. In Rio de Janeiro, landslides followed, burying hundreds of people. In Pakistan, the floods affected 20 million people. Meanwhile, other parts of the world suffer devastating droughts. Australia, Russia and East Africa have been hit in the last ten years. And then there are unexpected heat waves, such as in 2003 in Europe. That summer, 35,000 deaths were said to be heat-related.So, what is happening to our weather? Are these extreme events part of a natural cycle? Or are they caused by human activity and its effects on the Earth’s climate? Peter Miller says it’s probably a mixture of both of these things. On the one hand, the most important influences on weather events are natural cycles in the climate. Two of the most famous weather cycles, El Niño and La Niña, originate in the Pacific Ocean. The heat from the warm ocean rises high into the atmosphere and affects weather all around the world. On the other hand, the temperature of the Earth’s oceans is slowly but steadily going up. And this is a result of human activity. We are producing greenhouse gases that trap heat in the Earth’s atmosphere. This heat warms up the atmosphere, land and oceans. Warmer oceans produce more water vapour – think of heating a pan of water in your kitchen. Turn up the heat, it produces steam more quickly. Satellite data tells us that the water vapour in the atmosphere has gone up by four percent in 25 years. This warm, wet air turns into the rain, storms, hurricanes and typhoons that we are increasingly experiencing. Climate scientist, Michael Oppenheimer, says that we need to face the reality of climate change. And we also need to act now to save lives and money in the future.According to the passage, extreme weather is a problem because ______.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 2.9 K lượt xem 6 năm trước
Đề thi thử THPTGQ môn Toán cực cực hay có lời giải chi tiết(Đề 2)

Cho hàm số y=x3-3x2+2. Viết phương trình tiếp tuyến của đồ thị hàm số biết tiếp tuyến song song với đường thẳng y = 9x + 7 

Toán Tốt nghiệp THPT
Xem chi tiết 14.5 K lượt xem 6 năm trước
20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.    A rainbow is an optical display of color that usually appears in the sky when a beam of sunlight refracts through millions of raindrops. Each (31) ______ color from the spectrum is then sent to your eyes. For this to happen, the angle between the ray of light, the raindrop and the human eye must be between 40 and 42 degrees.    After studying rainbows in (32) ______, Sir Isaac Newton was able to explain how they are formed. However, he was color blind, so he had to rely on the eyes of his assistant, who could easily (33) ______ all the seven colors: red, orange, yellow, green, blue, indigo and violet. His assistant could also clearly tell the difference between indigo and violet.    There are two types of rainbows. Primary rainbows are the most common and have the most distinctive colors, with red appearing on the outside of the arc and violet on the inside. Secondary rainbows are unusual because the light is reflected twice within the raindrop before it (34) ______ a rainbow, so the colors are in reverse order and not as bright as primary rainbows.    There is a popular myth that if you reach the end of a rainbow, you will find a pot of gold waiting for you. In fact, it is impossible to do this, because a rainbow has no end - as you go towards the point where the rainbow seems to touch the ground, it moves away from you as quickly as you (35) ______.Điền ô số 32

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 299 lượt xem 6 năm trước
Dạng 1: Điều chế và thu khí trong phòng thí nghiệm

Trong phòng thí nghiệm, khí C được điều chế bằng bộ dụng cụ như hình vẽ:Khí C có thể là dãy các khí nào sau đây?

Hóa học Lớp 12
Xem chi tiết 642 lượt xem 6 năm trước
2.5. Xác định cấu tạo peptit qua phản ứng thủy phân

Cho tetrapeptit X có công thức cấu tạo như sau: H2NCH(CH3)CO-NHCH2CO-NHCH(COOH)CH2CH2CO-NHCH(CH3)COOH Thuỷ phân hoàn toàn X thu được bao nhiêu loại α-amino axit? 

Hóa học Lớp 12
Xem chi tiết 3.2 K lượt xem 6 năm trước
20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.    A rainbow is an optical display of color that usually appears in the sky when a beam of sunlight refracts through millions of raindrops. Each (31) ______ color from the spectrum is then sent to your eyes. For this to happen, the angle between the ray of light, the raindrop and the human eye must be between 40 and 42 degrees.    After studying rainbows in (32) ______, Sir Isaac Newton was able to explain how they are formed. However, he was color blind, so he had to rely on the eyes of his assistant, who could easily (33) ______ all the seven colors: red, orange, yellow, green, blue, indigo and violet. His assistant could also clearly tell the difference between indigo and violet.    There are two types of rainbows. Primary rainbows are the most common and have the most distinctive colors, with red appearing on the outside of the arc and violet on the inside. Secondary rainbows are unusual because the light is reflected twice within the raindrop before it (34) ______ a rainbow, so the colors are in reverse order and not as bright as primary rainbows.    There is a popular myth that if you reach the end of a rainbow, you will find a pot of gold waiting for you. In fact, it is impossible to do this, because a rainbow has no end - as you go towards the point where the rainbow seems to touch the ground, it moves away from you as quickly as you (35) ______.Điền ô số 31

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 447 lượt xem 6 năm trước
Tổng hợp đề thi thử THPTQG môn Vật lí năm 2020 cực hay có lời giải (Đề số 5)

Con lắc lò xo dao động điều hòa với biên độ A = 10 cm. Khi đi qua li độ x = 5 cm thì vật có động năng bằng 0,3 J. Độ cứng của lò xo là

Vật lý Tốt nghiệp THPT
Xem chi tiết 365 lượt xem 6 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.What is “extreme” weather? Why are people talking about it these days? “Extreme” weather is an unusual weather event such as rainfall, a drought or a heat wave in the wrong place or at the wrong time. In theory, they are very rare. But these days, our TV screens are constantly showing such extreme weather events. Take just three news stories from 2010: 28 centimetres of rain fell on Rio de Janeiro in 24 hours, Nashville, USA, had 33 centimetres of rain in two days and there was record rainfall in Pakistan.The effects of this kind of rainfall are dramatic and lethal. In Rio de Janeiro, landslides followed, burying hundreds of people. In Pakistan, the floods affected 20 million people. Meanwhile, other parts of the world suffer devastating droughts. Australia, Russia and East Africa have been hit in the last ten years. And then there are unexpected heat waves, such as in 2003 in Europe. That summer, 35,000 deaths were said to be heat-related.So, what is happening to our weather? Are these extreme events part of a natural cycle? Or are they caused by human activity and its effects on the Earth’s climate? Peter Miller says it’s probably a mixture of both of these things. On the one hand, the most important influences on weather events are natural cycles in the climate. Two of the most famous weather cycles, El Niño and La Niña, originate in the Pacific Ocean. The heat from the warm ocean rises high into the atmosphere and affects weather all around the world. On the other hand, the temperature of the Earth’s oceans is slowly but steadily going up. And this is a result of human activity. We are producing greenhouse gases that trap heat in the Earth’s atmosphere. This heat warms up the atmosphere, land and oceans. Warmer oceans produce more water vapour – think of heating a pan of water in your kitchen. Turn up the heat, it produces steam more quickly. Satellite data tells us that the water vapour in the atmosphere has gone up by four percent in 25 years. This warm, wet air turns into the rain, storms, hurricanes and typhoons that we are increasingly experiencing. Climate scientist, Michael Oppenheimer, says that we need to face the reality of climate change. And we also need to act now to save lives and money in the future.What caused thousands of deaths in 2003?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1 K lượt xem 6 năm trước
Bài 8: Điện năng. Công suất điện.

Dùng ấm điện có ghi 220V - 1000W ở điện áp 220V để đun sôi 2 lít nước từ nhiệt độ 25oC. Biết hiệu suất của ấm là 90%, nhiệt dung riêng của nước là 4190 J/(kg.K), thời gian đun nước là

Vật lý Lớp 11
Xem chi tiết 4.1 K lượt xem 6 năm trước
2.5. Xác định cấu tạo peptit qua phản ứng thủy phân

Thủy phân hoàn toàn 1 mol pentapeptit Y, thu được 3 mol glyxin, 1 mol valin và 1 mol alanin. Khi thủy phân không hoàn toàn Y thu được các đipeptit Ala-Gly, Gly-Val và 1 tripeptit Gly-Gly-Gly. Cấu tạo của Y là 

Hóa học Lớp 12
Xem chi tiết 2.4 K lượt xem 6 năm trước
Tổng hợp đề thi thử THPTQG môn Vật Lí cực hay có lời giải (Đề số 1)

Một chất điểm dao động điều hòa với biên độ 6 cm và chu kì 0,5 s. Trong khoảng thời gian ngắn nhất đi từ vị trí x = 6 cm đến vị trí x = -3 cm, vật có tốc độ trung bình

Vật lý Tốt nghiệp THPT
Xem chi tiết 13.2 K lượt xem 6 năm trước
Tổng hợp đề thi thử THPTQG môn Vật lí năm 2020 cực hay có lời giải (Đề số 5)

Một con lắc đơn gồm quả nặng có khối lượng m và dây treo có chiều dài l có thể thay đổi được. Nếu chiều dài dây treo là l1, thì chu kì dao động của con lắc là 1 s. Nếu chiều dài dây treo là l2 thì chu kì dao động của con lắc là 2 s. Nếu chiều dài con lắc là l3 = 4l1 + 3l2 thì chu kì dao động của con lắc là

Vật lý Tốt nghiệp THPT
Xem chi tiết 482 lượt xem 6 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.What is “extreme” weather? Why are people talking about it these days? “Extreme” weather is an unusual weather event such as rainfall, a drought or a heat wave in the wrong place or at the wrong time. In theory, they are very rare. But these days, our TV screens are constantly showing such extreme weather events. Take just three news stories from 2010: 28 centimetres of rain fell on Rio de Janeiro in 24 hours, Nashville, USA, had 33 centimetres of rain in two days and there was record rainfall in Pakistan.The effects of this kind of rainfall are dramatic and lethal. In Rio de Janeiro, landslides followed, burying hundreds of people. In Pakistan, the floods affected 20 million people. Meanwhile, other parts of the world suffer devastating droughts. Australia, Russia and East Africa have been hit in the last ten years. And then there are unexpected heat waves, such as in 2003 in Europe. That summer, 35,000 deaths were said to be heat-related.So, what is happening to our weather? Are these extreme events part of a natural cycle? Or are they caused by human activity and its effects on the Earth’s climate? Peter Miller says it’s probably a mixture of both of these things. On the one hand, the most important influences on weather events are natural cycles in the climate. Two of the most famous weather cycles, El Niño and La Niña, originate in the Pacific Ocean. The heat from the warm ocean rises high into the atmosphere and affects weather all around the world. On the other hand, the temperature of the Earth’s oceans is slowly but steadily going up. And this is a result of human activity. We are producing greenhouse gases that trap heat in the Earth’s atmosphere. This heat warms up the atmosphere, land and oceans. Warmer oceans produce more water vapour – think of heating a pan of water in your kitchen. Turn up the heat, it produces steam more quickly. Satellite data tells us that the water vapour in the atmosphere has gone up by four percent in 25 years. This warm, wet air turns into the rain, storms, hurricanes and typhoons that we are increasingly experiencing. Climate scientist, Michael Oppenheimer, says that we need to face the reality of climate change. And we also need to act now to save lives and money in the future.The word -lethal‖ in the second paragraph probably means ______.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.1 K lượt xem 6 năm trước
200 bài trắc nghiệm Oxyz cực hay có lời giải chi tiết (P2)

Trong không gian Oxyz, mặt cầu tâm I(-1;2;3) và đi qua điểm A(2;0;0) có phương trình là:

Toán Lớp 12
Xem chi tiết 370 lượt xem 6 năm trước
Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 15)

Trong các dung dịch sau: NaCl, NaOH, HCl, CH3COONa, CH3COONa, CH3COOH, C2H5OH, glucozơ, fomon và phenyl amoniclorua. Hãy cho biết có bao nhiêu dung dịch dẫn được điện?

Hóa học Tốt nghiệp THPT
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Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.What is “extreme” weather? Why are people talking about it these days? “Extreme” weather is an unusual weather event such as rainfall, a drought or a heat wave in the wrong place or at the wrong time. In theory, they are very rare. But these days, our TV screens are constantly showing such extreme weather events. Take just three news stories from 2010: 28 centimetres of rain fell on Rio de Janeiro in 24 hours, Nashville, USA, had 33 centimetres of rain in two days and there was record rainfall in Pakistan.The effects of this kind of rainfall are dramatic and lethal. In Rio de Janeiro, landslides followed, burying hundreds of people. In Pakistan, the floods affected 20 million people. Meanwhile, other parts of the world suffer devastating droughts. Australia, Russia and East Africa have been hit in the last ten years. And then there are unexpected heat waves, such as in 2003 in Europe. That summer, 35,000 deaths were said to be heat-related.So, what is happening to our weather? Are these extreme events part of a natural cycle? Or are they caused by human activity and its effects on the Earth’s climate? Peter Miller says it’s probably a mixture of both of these things. On the one hand, the most important influences on weather events are natural cycles in the climate. Two of the most famous weather cycles, El Niño and La Niña, originate in the Pacific Ocean. The heat from the warm ocean rises high into the atmosphere and affects weather all around the world. On the other hand, the temperature of the Earth’s oceans is slowly but steadily going up. And this is a result of human activity. We are producing greenhouse gases that trap heat in the Earth’s atmosphere. This heat warms up the atmosphere, land and oceans. Warmer oceans produce more water vapour – think of heating a pan of water in your kitchen. Turn up the heat, it produces steam more quickly. Satellite data tells us that the water vapour in the atmosphere has gone up by four percent in 25 years. This warm, wet air turns into the rain, storms, hurricanes and typhoons that we are increasingly experiencing. Climate scientist, Michael Oppenheimer, says that we need to face the reality of climate change. And we also need to act now to save lives and money in the future.It is stated in the passage that extreme weather is ______.

Tiếng Anh Tốt nghiệp THPT
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2.5. Xác định cấu tạo peptit qua phản ứng thủy phân

Thủy phân hoàn toàn 8,6 gam một peptit X thu được hỗn hợp sản phẩm gồm 4,5 gam glyxin, 3,56 gam alanin và 2,34 gam valin. Thủy phân không hoàn toàn X thu được tripeptit Ala-Val-Gly và đipeptit Gly-Ala, không thu được đipeptit Ala-Gly. Công thức cấu tạo của X là 

Hóa học Lớp 12
Xem chi tiết 783 lượt xem 6 năm trước
Bộ đề luyện thi Hóa Học cực hay có lời giải chi tiết (Đề số 15)

Cho butan qua xúc tác ( ở nhiệt độ cao ) thu được hỗn hợp X gồm C4H10, C4H8, C4H6 và H2. Tỉ khối của X so với butan là 0,4. Nếu cho 0,6 mol X tác dụng với dung dịch nước brom dư thì số mol brom tối đa phản ứng là

Hóa học Tốt nghiệp THPT
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Tổng hợp đề thi thử THPTQG môn Vật lí năm 2020 cực hay có lời giải (Đề số 5)

Hai điện tích điểm giống nhau đặt trong chân không cách nhau một khoảng r1 = 2 cm. Lực đẩy giữa chúng là F1 = 1,6.10-4 N. Để lực tương tác giữa hai điện tích đó bằng F2 = 2,5.10-4 N thì khoảng cách giữa chúng là

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Bài 8: Điện năng. Công suất điện.

Một bếp điện đun hai lít nước ở nhiệt độ t1 = 20oC. Muốn đun sôi lượng nước đó trong 20 phút thì bếp điện phải có công suất là bao nhiêu ? Biết nhiệt dung riêng của nước c = 4,18 kJ/(kg.K) và hiệu suất của bếp điện H = 70%.

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Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 15)

Cho bột Fe vào dung dịch gồm AgNO3 và Cu(NO3)2. Sau khi các phản ứng xảy ra hoàn toàn, thu được dung dịch X gồm hai muối và chất rắn Y gồm hai kim loại. Hai muối trong X và hai kim loại trong Y lần lượt là

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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.    Duncan Phyfe made some of the most beautiful furniture found in America. His family name was originally Fife, and he was born in Scotland in 1768. In 1784, the Fife family immigrated to Albany, New York where Duncan’s father opened a cabinetmaking shop. Duncan followed his father’s footsteps and was apprenticed to a cabinetmaker. After completing his training, Duncan moved to New York City.    Duncan Fife was first mentioned in the 1792 NYC Directory as a furniture “joiner” in business at 2 Broad Street. Two years later, he moved, expanded his business, and changed his name to Phyfe. He was a quiet-living, God-fearing young man who felt his new name would probably appeal to potential customers who were definitely anti-British in this post-Revolutionary War period.    Duncan Phyfe’s name distinguished him from his contemporaries. Although the new spelling helped him better compete with French emigrant craftsmen, his new name had more to do with hanging it on a sign over his door stoop.    The artisans and merchants who came to America discovered a unique kind of freedom. They were no longer restricted by class and guild traditions of Europe. For the first time in history, a man learned that by working hard, he could build his business based on his own name and reputation and quality of work.    Phyfe’s workshop apparently took off immediately. At the peak of his success, Phyfe employed 100 craftsmen. Some economic historians point to Phyfe as having employed division of labor and an assembly line. What his workshop produced shows Phyfe’s absolute dedication to quality in workmanship. Each piece of furniture was made of the best available materials. He was reported to have paid $1,000 for a single Santo Domingo mahogany log.Phyfe did not create new designs. Rather, he borrowed from a broad range of the period’s classical styles, Empire, Sheraton, Regency, and French Classical among them. Nevertheless, Phyfe’s high quality craftsmanship established him as America’s patriotic interpreter of European design in the late eighteenth and early nineteenth centuries.           Although the number of pieces produced by Duncan Phyfe’s workshop is enormous, comparatively few marked or labeled pieces have been found extant. In antiques shops and auctions, collectors have paid $11,000 for a card table, $24,200 for a tea table, and $93,500 for a sewing tableThe author implies that ______.

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Đề thi thử THPTGQ môn Toán cực cực hay có lời giải chi tiết(Đề 2)

Cho dãy số un  với un=4n2+n+2an2+5.  Để dãy số đã cho có giới hạn bằng 2, giá trị của a là

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Dạng 1: Điều chế và thu khí trong phòng thí nghiệm

Trong phòng thí nghiệm, bộ dụng vụ vẽ dưới đây có thể dùng để điều chế những chất khí nào trong các chất khí sau: Cl2, O2, NH3, SO2, CO2, H2, C2H4?

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Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.It used to be that people would drink coffee or tea in the morning to pick them up and get them going for the day. Then cola drinks hit the market. With lots of caffeine and sugar, these beverages soon became the pick-me-up of choice for many adults and teenagers. Now drink companies are putting out so-called "energy drinks." These beverages have the specific aim of giving tired consumers more energy. One example of a popular energy drink is Red Bull. The company that puts out this beverage has stated in interviews that Red Bull is not a thirst quencher. Nor is it meant to be a fluid replacement drink for athletes. Instead, the beverage is meant to revitalize a tired consumer’s body and mind. In order to do this, the makers of Red Bull, and other energy drinks, typically add vitamins and certain chemicals to their beverages. The added chemicals are like chemicals that the body naturally produces for energy. The vitamins, chemicals, caffeine, and sugar found in these beverages all seem like a sure bet to give a person energy.Health professionals are not so sure, though. For one thing, there is not enough evidence to show that all of the vitamins added to energy drinks actually raise a person’s energy level. Another problem is that there are so many things in the beverages. Nobody knows for sure how all of the ingredients in energy drinks work together. Dr. Brent Bauer, one of the directors at the Mayo Clinic in the US, cautions people about believing all the claims energy drinks make. He says, - It is plausible if you put all these things together, you will get a good result.” However, Dr. Bauer adds the mix of ingredients could also have a negative impact on the body. - We just don’t know at this point,” he says.What is the main idea of this passage?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 2 K lượt xem 6 năm trước
2.5. Xác định cấu tạo peptit qua phản ứng thủy phân

Thủy phân từng phần một pentapeptit thu được các đipeptit và tripeptit sau: X-T, Z-Y, T-Z, Y-E và T-Z-Y (X, Y, Z, T, E là kí hiệu các gốc α-amino axit). Trình tự các amino axit trên là: 

Hóa học Lớp 12
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Bộ đề luyện thi Hóa Học cực hay có lời giải chi tiết (Đề số 15)

Kim loại nào sau đây có tính khử mạnh nhất

Hóa học Tốt nghiệp THPT
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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.    Duncan Phyfe made some of the most beautiful furniture found in America. His family name was originally Fife, and he was born in Scotland in 1768. In 1784, the Fife family immigrated to Albany, New York where Duncan’s father opened a cabinetmaking shop. Duncan followed his father’s footsteps and was apprenticed to a cabinetmaker. After completing his training, Duncan moved to New York City.    Duncan Fife was first mentioned in the 1792 NYC Directory as a furniture “joiner” in business at 2 Broad Street. Two years later, he moved, expanded his business, and changed his name to Phyfe. He was a quiet-living, God-fearing young man who felt his new name would probably appeal to potential customers who were definitely anti-British in this post-Revolutionary War period.    Duncan Phyfe’s name distinguished him from his contemporaries. Although the new spelling helped him better compete with French emigrant craftsmen, his new name had more to do with hanging it on a sign over his door stoop.    The artisans and merchants who came to America discovered a unique kind of freedom. They were no longer restricted by class and guild traditions of Europe. For the first time in history, a man learned that by working hard, he could build his business based on his own name and reputation and quality of work.    Phyfe’s workshop apparently took off immediately. At the peak of his success, Phyfe employed 100 craftsmen. Some economic historians point to Phyfe as having employed division of labor and an assembly line. What his workshop produced shows Phyfe’s absolute dedication to quality in workmanship. Each piece of furniture was made of the best available materials. He was reported to have paid $1,000 for a single Santo Domingo mahogany log.Phyfe did not create new designs. Rather, he borrowed from a broad range of the period’s classical styles, Empire, Sheraton, Regency, and French Classical among them. Nevertheless, Phyfe’s high quality craftsmanship established him as America’s patriotic interpreter of European design in the late eighteenth and early nineteenth centuries.           Although the number of pieces produced by Duncan Phyfe’s workshop is enormous, comparatively few marked or labeled pieces have been found extant. In antiques shops and auctions, collectors have paid $11,000 for a card table, $24,200 for a tea table, and $93,500 for a sewing tableBased on the information in the passage, what can be inferred about Duncan Phyfe’s death?

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Tổng hợp đề thi thử THPTQG môn Vật lí năm 2020 cực hay có lời giải (Đề số 5)

Một con lắc đơn dao động điều hòa với chu kì T = 4 s, thời gian ngắn nhất để con lắc đi từ vị trí cân bằng đến vị trí biên là

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Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.It used to be that people would drink coffee or tea in the morning to pick them up and get them going for the day. Then cola drinks hit the market. With lots of caffeine and sugar, these beverages soon became the pick-me-up of choice for many adults and teenagers. Now drink companies are putting out so-called "energy drinks." These beverages have the specific aim of giving tired consumers more energy. One example of a popular energy drink is Red Bull. The company that puts out this beverage has stated in interviews that Red Bull is not a thirst quencher. Nor is it meant to be a fluid replacement drink for athletes. Instead, the beverage is meant to revitalize a tired consumer’s body and mind. In order to do this, the makers of Red Bull, and other energy drinks, typically add vitamins and certain chemicals to their beverages. The added chemicals are like chemicals that the body naturally produces for energy. The vitamins, chemicals, caffeine, and sugar found in these beverages all seem like a sure bet to give a person energy.Health professionals are not so sure, though. For one thing, there is not enough evidence to show that all of the vitamins added to energy drinks actually raise a person’s energy level. Another problem is that there are so many things in the beverages. Nobody knows for sure how all of the ingredients in energy drinks work together. Dr. Brent Bauer, one of the directors at the Mayo Clinic in the US, cautions people about believing all the claims energy drinks make. He says, - It is plausible if you put all these things together, you will get a good result.” However, Dr. Bauer adds the mix of ingredients could also have a negative impact on the body. - We just don’t know at this point,” he says.Which of the following is NOT true according to the passage?

Tiếng Anh Tốt nghiệp THPT
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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.    Duncan Phyfe made some of the most beautiful furniture found in America. His family name was originally Fife, and he was born in Scotland in 1768. In 1784, the Fife family immigrated to Albany, New York where Duncan’s father opened a cabinetmaking shop. Duncan followed his father’s footsteps and was apprenticed to a cabinetmaker. After completing his training, Duncan moved to New York City.    Duncan Fife was first mentioned in the 1792 NYC Directory as a furniture “joiner” in business at 2 Broad Street. Two years later, he moved, expanded his business, and changed his name to Phyfe. He was a quiet-living, God-fearing young man who felt his new name would probably appeal to potential customers who were definitely anti-British in this post-Revolutionary War period.    Duncan Phyfe’s name distinguished him from his contemporaries. Although the new spelling helped him better compete with French emigrant craftsmen, his new name had more to do with hanging it on a sign over his door stoop.    The artisans and merchants who came to America discovered a unique kind of freedom. They were no longer restricted by class and guild traditions of Europe. For the first time in history, a man learned that by working hard, he could build his business based on his own name and reputation and quality of work.    Phyfe’s workshop apparently took off immediately. At the peak of his success, Phyfe employed 100 craftsmen. Some economic historians point to Phyfe as having employed division of labor and an assembly line. What his workshop produced shows Phyfe’s absolute dedication to quality in workmanship. Each piece of furniture was made of the best available materials. He was reported to have paid $1,000 for a single Santo Domingo mahogany log.Phyfe did not create new designs. Rather, he borrowed from a broad range of the period’s classical styles, Empire, Sheraton, Regency, and French Classical among them. Nevertheless, Phyfe’s high quality craftsmanship established him as America’s patriotic interpreter of European design in the late eighteenth and early nineteenth centuries.           Although the number of pieces produced by Duncan Phyfe’s workshop is enormous, comparatively few marked or labeled pieces have been found extant. In antiques shops and auctions, collectors have paid $11,000 for a card table, $24,200 for a tea table, and $93,500 for a sewing tableIn his business, Duncan Phyfe used all of the following EXCEPT ______.

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp đề thi thử THPTQG môn Vật lí năm 2020 cực hay có lời giải (Đề số 5)

Xét nguyên tử Hidro theo mẫu nguyên tử Bo. Cho biết bán kính Bo r0 = 5,3.10-11 m. Quỹ đạo dừng M của electron trong nguyên tử có bán kính

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Xem chi tiết 496 lượt xem 6 năm trước
2.5. Xác định cấu tạo peptit qua phản ứng thủy phân

Arg, Pro và Ser có trong thành phần cấu tạo của nonapeptit brađikinin. Thủy phân brađikinin sinh ra Pro-Pro-Gly, Ser-Pro-Phe, Gly-Phe-Ser, Pro-Phe-Arg, Arg-Pro-Pro, Pro-Gly-Phe, Phe-Ser-Pro. Cho biết trình tự các amino axit trong phân tử brađikinin ? 

Hóa học Lớp 12
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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.    Duncan Phyfe made some of the most beautiful furniture found in America. His family name was originally Fife, and he was born in Scotland in 1768. In 1784, the Fife family immigrated to Albany, New York where Duncan’s father opened a cabinetmaking shop. Duncan followed his father’s footsteps and was apprenticed to a cabinetmaker. After completing his training, Duncan moved to New York City.    Duncan Fife was first mentioned in the 1792 NYC Directory as a furniture “joiner” in business at 2 Broad Street. Two years later, he moved, expanded his business, and changed his name to Phyfe. He was a quiet-living, God-fearing young man who felt his new name would probably appeal to potential customers who were definitely anti-British in this post-Revolutionary War period.    Duncan Phyfe’s name distinguished him from his contemporaries. Although the new spelling helped him better compete with French emigrant craftsmen, his new name had more to do with hanging it on a sign over his door stoop.    The artisans and merchants who came to America discovered a unique kind of freedom. They were no longer restricted by class and guild traditions of Europe. For the first time in history, a man learned that by working hard, he could build his business based on his own name and reputation and quality of work.    Phyfe’s workshop apparently took off immediately. At the peak of his success, Phyfe employed 100 craftsmen. Some economic historians point to Phyfe as having employed division of labor and an assembly line. What his workshop produced shows Phyfe’s absolute dedication to quality in workmanship. Each piece of furniture was made of the best available materials. He was reported to have paid $1,000 for a single Santo Domingo mahogany log.Phyfe did not create new designs. Rather, he borrowed from a broad range of the period’s classical styles, Empire, Sheraton, Regency, and French Classical among them. Nevertheless, Phyfe’s high quality craftsmanship established him as America’s patriotic interpreter of European design in the late eighteenth and early nineteenth centuries.           Although the number of pieces produced by Duncan Phyfe’s workshop is enormous, comparatively few marked or labeled pieces have been found extant. In antiques shops and auctions, collectors have paid $11,000 for a card table, $24,200 for a tea table, and $93,500 for a sewing tableWhich choice is closest in meaning to the word “guild” in paragraph 4?

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Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 15)

Khi cho ankan X (trong phân tử có phần trăm khối lượng hiđro bằng 16,28%) tác dụng với khí Cl2 theo tỉ lệ mol 1:1 (trong điều kiện chiếu sáng) chỉ thu được hai dẫn xuất monoclo đồng phân của nhau. Tên của X là

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Bộ đề luyện thi Hóa Học cực hay có lời giải chi tiết (Đề số 15)

Khử m gam hỗn hợp X gồm các oxit CuO, FeO, Fe3O4 và Fe2O3 bằng khí CO ở nhiệt độ cao, người ta thu được 40 gam hỗn hợp chất rắn Y và 13,2 gam khí CO2. Giá trị của m là

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Đề thi thử THPTGQ môn Toán cực cực hay có lời giải chi tiết(Đề 2)

Để trang hoàng cho căn hộ của mình, An quyết định tô màu một miếng bìa hình vuông cạnh bằng 1. Bạn ấy tô màu đỏ các hình vuông nhỏ được đánh số lần lượt là 1,2,3,....,n,..., trong đó cạnh của hình vuông kế tiếp bằng một nửa hình vuông trước đó (như hình bên). Giả sử quy trình tô màu của An có thể tạo ra vô hạn. Hỏi bạn An tô màu đến hình vuông thứ mấy thì diện tích của hình vuông được tô nhỏ hơn 11000 

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Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.It used to be that people would drink coffee or tea in the morning to pick them up and get them going for the day. Then cola drinks hit the market. With lots of caffeine and sugar, these beverages soon became the pick-me-up of choice for many adults and teenagers. Now drink companies are putting out so-called "energy drinks." These beverages have the specific aim of giving tired consumers more energy. One example of a popular energy drink is Red Bull. The company that puts out this beverage has stated in interviews that Red Bull is not a thirst quencher. Nor is it meant to be a fluid replacement drink for athletes. Instead, the beverage is meant to revitalize a tired consumer’s body and mind. In order to do this, the makers of Red Bull, and other energy drinks, typically add vitamins and certain chemicals to their beverages. The added chemicals are like chemicals that the body naturally produces for energy. The vitamins, chemicals, caffeine, and sugar found in these beverages all seem like a sure bet to give a person energy.Health professionals are not so sure, though. For one thing, there is not enough evidence to show that all of the vitamins added to energy drinks actually raise a person’s energy level. Another problem is that there are so many things in the beverages. Nobody knows for sure how all of the ingredients in energy drinks work together. Dr. Brent Bauer, one of the directors at the Mayo Clinic in the US, cautions people about believing all the claims energy drinks make. He says, - It is plausible if you put all these things together, you will get a good result.” However, Dr. Bauer adds the mix of ingredients could also have a negative impact on the body. - We just don’t know at this point,” he says.What has Dr. Bauer probably researched?

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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 20)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.    Duncan Phyfe made some of the most beautiful furniture found in America. His family name was originally Fife, and he was born in Scotland in 1768. In 1784, the Fife family immigrated to Albany, New York where Duncan’s father opened a cabinetmaking shop. Duncan followed his father’s footsteps and was apprenticed to a cabinetmaker. After completing his training, Duncan moved to New York City.    Duncan Fife was first mentioned in the 1792 NYC Directory as a furniture “joiner” in business at 2 Broad Street. Two years later, he moved, expanded his business, and changed his name to Phyfe. He was a quiet-living, God-fearing young man who felt his new name would probably appeal to potential customers who were definitely anti-British in this post-Revolutionary War period.    Duncan Phyfe’s name distinguished him from his contemporaries. Although the new spelling helped him better compete with French emigrant craftsmen, his new name had more to do with hanging it on a sign over his door stoop.    The artisans and merchants who came to America discovered a unique kind of freedom. They were no longer restricted by class and guild traditions of Europe. For the first time in history, a man learned that by working hard, he could build his business based on his own name and reputation and quality of work.    Phyfe’s workshop apparently took off immediately. At the peak of his success, Phyfe employed 100 craftsmen. Some economic historians point to Phyfe as having employed division of labor and an assembly line. What his workshop produced shows Phyfe’s absolute dedication to quality in workmanship. Each piece of furniture was made of the best available materials. He was reported to have paid $1,000 for a single Santo Domingo mahogany log.Phyfe did not create new designs. Rather, he borrowed from a broad range of the period’s classical styles, Empire, Sheraton, Regency, and French Classical among them. Nevertheless, Phyfe’s high quality craftsmanship established him as America’s patriotic interpreter of European design in the late eighteenth and early nineteenth centuries.           Although the number of pieces produced by Duncan Phyfe’s workshop is enormous, comparatively few marked or labeled pieces have been found extant. In antiques shops and auctions, collectors have paid $11,000 for a card table, $24,200 for a tea table, and $93,500 for a sewing tableWhich choice does the word “it” in paragraph 3 refer to?

Tiếng Anh Tốt nghiệp THPT
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Chương V. CHẤT KHÍ

Ở nhiệt độ 0  và áp suât 760 mmHg, 22,4 lít khí ôxi chứa 6,02.1023 phân tử ôxi. Coi phân tử ôxi như một quả cầu có bán kính r=10-10m. Thể tích riêng của các phân tử khí ôxi nhỏ hơn thể tích bình chứa 

Vật lý Lớp 10
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