Danh sách câu hỏi ( Có 2,195,674 câu hỏi trên 43,914 trang )

BÀI TẬP LÝ THUYẾT

Trong quá trình điện phân dung dịch KCl, quá trình nào sau đây xảy ra ở cực dương (anot)

Hóa học Lớp 12
Xem chi tiết 6 K lượt xem 5 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 3)

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.Rain forests cover less than six percent of the earth’s area, but they have 100,000 kinds of all the kinds of plants on the earth. Three-fourths of known kinds of plants and animals call the rain forest their home. Twenty percent of our different kinds of medicine comes from rain forests. The glues on an envelope and in shoes come from tropical plants. Rain forests provide materials for hundreds of other products.Rain forests are also very important to the world’s climate. The Amazon rain forest alone receives about thirty to forty percent of the total rainfall on the earth and products about the same percentage of the world oxygen. Some scientists believe that the decreasing size of rain forests will affect the climate on the earth, making it uncomfortable or even dangerous for life.Saving rain forests is an international problem. One country, or even a few countries, cannot solve the problem alone. The nations of the world must work together to find a solution before it is too late.According to the passage, what must the nations of the world do to find a solution?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 650 lượt xem 5 năm trước
30 đề thi thử đề thi thử THPTQG môn Tiếng Anh có lời giải chi tiết (Đề số 26)

According to the passage, what did Carson primarily study at Johns Hopkins University?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 323 lượt xem 5 năm trước
Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P12)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word for each of the blanks.THE FIRST WOMAN SCIENTISTHypatia was born in Alexandria, in Egypt, in 370 A.D. For many centuries, she was (16)          only   woman scientist to have a place in the history books.Hypatia's father was director of Alexandria University, and he (17)             sure his daughter had the best education available. This was unusual, as most women then had few (18)           to study.After studying in Athens and Rome, Hypatia returned to Alexandria (19)       she began teaching mathematics. She soon became famous (20)           her knowledge of new ideas.We have no copies of her book, (21)       we know that she wrote several important mathematical works. Hypatia was also interested in technology and (22)       several scientific tools to help with her work. At the (23)       , many rulers were afraid of science, and (24)        connected with it was in danger. One day in March 415, Hypatia (25)           attacked in the street and killed.Điền vào ô 20

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 3.8 K lượt xem 5 năm trước
BÀI TẬP LÝ THUYẾT

Điều nào là không đúng trong các điều sau:

Hóa học Lớp 12
Xem chi tiết 13.1 K lượt xem 5 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 3)

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.Rain forests cover less than six percent of the earth’s area, but they have 100,000 kinds of all the kinds of plants on the earth. Three-fourths of known kinds of plants and animals call the rain forest their home. Twenty percent of our different kinds of medicine comes from rain forests. The glues on an envelope and in shoes come from tropical plants. Rain forests provide materials for hundreds of other products.Rain forests are also very important to the world’s climate. The Amazon rain forest alone receives about thirty to forty percent of the total rainfall on the earth and products about the same percentage of the world oxygen. Some scientists believe that the decreasing size of rain forests will affect the climate on the earth, making it uncomfortable or even dangerous for life.Saving rain forests is an international problem. One country, or even a few countries, cannot solve the problem alone. The nations of the world must work together to find a solution before it is too late.According to some scientists, what will the decreasing size of rain forests affect on the earth?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.3 K lượt xem 5 năm trước
KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P12)

Safety should take _________over all other matters in the workplace

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.4 K lượt xem 5 năm trước
Đề luyện thi THPT Quốc Gia - Năm 2020 Môn thi: TIẾNG ANH (Đề số 3)

Read the following text then answer the questions that followed by circling its corresponding letter marked A, B, C or D from 43 to 50. Since water is the basis of life, composing the greater part of the tissues of all living things, the crucial problem of desert animals is to survive in a world where sources of flowing water are rare. And since man’s inexorable necessity is to absorb large quantities of water at frequent intervals, he can scarcely comprehend that many creatures of the desert pass their entire lives without a single drop. Uncompromising as it is, the desert has not a limited life but only those forms unable to withstand its desiccating effects. No moist skinned, water-loving animals can exist there. Few large animals are found. The giants of the North American desert are the deer, the coyote, and the bobcat. Since desert country is open, it holds more swift-footed running and leaping creatures than the tangled forest. Its population is largely nocturnal, silent, filled with reticence, and ruled by stealth. Yet they are not emaciated. Having adapted to their austere environment, they are as healthy as animals anywhere else in the world. The secret of their adjustment lies in the combination of behavior and physiology. None could survive, like mad dogs and Englishmen, if they went out in the midday sun, many would die in a matter of minutes. So most of them pass the burning hours asleep in cool, humid burrows underneath the ground, emerging to hunt only by night. The surface of the sun-baked desert averages around 150 degrees, but 18 inches down the temperature is only 60 degrees.The word “tissues” in the passage mostly means _______.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 2.2 K lượt xem 5 năm trước
BÀI TẬP LÝ THUYẾT

Phản ứng điện phân nóng chảy nào dưới đây bị viết sai sản phẩm?

Hóa học Lớp 12
Xem chi tiết 11.5 K lượt xem 5 năm trước
Đề luyện thi THPT quốc gia môn tiếng anh có lời giải (Đề số 04)

Read the passage and choose the best option to complete each blank.Any change in one part of an ecosystem can cause changes in other parts. Droughts, storms and fires can change ecosystems. Some changes ____(46)___ ecosystems. If there is too little rainfall, plants will not have enough water to live. If a kind of plant dies off, the animals____(47)___feed on it may also die or move away. Some changes are good for ecosystems. Some pine forests need fires for the pine trees to reproduce. The seeds are sealed inside pinecones. Heat from a forest fire melts the seal and lets the seeds ____(48)___. Polluting the air, soil, and water can harm ecosystems. Building dams on rivers for electric power and irrigation can harm ecosystems ____(49)___ the rivers. Bulldozing wetlands and cutting down forests destroy ecosystems. Ecologists are working with companies and governments to find better ways of ___(50)____ fish, cutting down trees, and building dams. They are looking for ways to get food, lumber, and other products for people without causing harm to ecosystems Điền ô số 50

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 360 lượt xem 5 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 3)

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.Rain forests cover less than six percent of the earth’s area, but they have 100,000 kinds of all the kinds of plants on the earth. Three-fourths of known kinds of plants and animals call the rain forest their home. Twenty percent of our different kinds of medicine comes from rain forests. The glues on an envelope and in shoes come from tropical plants. Rain forests provide materials for hundreds of other products.Rain forests are also very important to the world’s climate. The Amazon rain forest alone receives about thirty to forty percent of the total rainfall on the earth and products about the same percentage of the world oxygen. Some scientists believe that the decreasing size of rain forests will affect the climate on the earth, making it uncomfortable or even dangerous for life.Saving rain forests is an international problem. One country, or even a few countries, cannot solve the problem alone. The nations of the world must work together to find a solution before it is too late.What percent of the total rainfall on the earth does the Amazon rain forests receive?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 582 lượt xem 5 năm trước
Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 9)

Cho các phát biểu sau:(a) Anbunin là protein hình cầu, không tan trong nuớc.(b) Animoaxit là hợp chất hữu cơ tạp chức.(c) Saccarozo thuộc loại đisaccarit.(d) Công thức tổng quát của amin no, mạch hở đơn chức là CnH2n+3N.(e) Tất cả các peptit đều có phản ứng với Cu(OH)2 tạo hợp chất màu tím.(f) Trong phân tử tetrapeptit mạch hở có 3 liên kết peptit.(g) Lực bazơ của metylamin mạnh hơn đimetylamin.Số phát biểu đúng là

Hóa học Tốt nghiệp THPT
Xem chi tiết 419 lượt xem 5 năm trước
30 đề thi thử đề thi thử THPTQG môn Tiếng Anh có lời giải chi tiết (Đề số 26)

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.Rachel Carson was born in 1907 in Springsdale, Pennsylvania. She studied biology at college and zoology at Johns Hopkins University, where she received her master’s degree in 1933. In 1936, she was hired by the U.S. Fish and Wildlife Service, where she worked most of her life.Carson’s first book, Under the Sea Wind, was published in 1941. It received excellent reviews, but sales were poor until it was reissued in 1952. In that year she published The Sea Around Us, which provided a fascinating look beneath the ocean’s surface, emphasizing human history as well as geology and marine biology. Her imagery and language had a poetic quality. Carson consulted no less than 1,000 printed sources. She had voluminous correspondence and frequent discussions with experts in the field. However, she always realized the limitations of her nontechnical readers.In 1962, Carson published Silent Spring, a book that sparked considerable controversy. It proved how much harm was done by the uncontrolled, reckless use of insecticides. She detailed how they poison the food supply of animals, kill birds and fish, and contaminate human food. At the time, spokesmen for the chemical industry mounted personal attacks against Carson and issued propaganda to indicate that her findings were flawed. However, her work was proved by a 1963 report of the President’s Science Advisory Committee.(Source: TOEFL Reading)The passage mainly discusses Rachel Carson’s work 

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 524 lượt xem 5 năm trước
Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P12)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word for each of the blanks.THE FIRST WOMAN SCIENTISTHypatia was born in Alexandria, in Egypt, in 370 A.D. For many centuries, she was (16)          only   woman scientist to have a place in the history books.Hypatia's father was director of Alexandria University, and he (17)             sure his daughter had the best education available. This was unusual, as most women then had few (18)           to study.After studying in Athens and Rome, Hypatia returned to Alexandria (19)       she began teaching mathematics. She soon became famous (20)           her knowledge of new ideas.We have no copies of her book, (21)       we know that she wrote several important mathematical works. Hypatia was also interested in technology and (22)       several scientific tools to help with her work. At the (23)       , many rulers were afraid of science, and (24)        connected with it was in danger. One day in March 415, Hypatia (25)           attacked in the street and killed.Điền vào ô 19

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1 K lượt xem 5 năm trước
Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P12)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word for each of the blanks.THE FIRST WOMAN SCIENTISTHypatia was born in Alexandria, in Egypt, in 370 A.D. For many centuries, she was (16)          only   woman scientist to have a place in the history books.Hypatia's father was director of Alexandria University, and he (17)             sure his daughter had the best education available. This was unusual, as most women then had few (18)           to study.After studying in Athens and Rome, Hypatia returned to Alexandria (19)       she began teaching mathematics. She soon became famous (20)           her knowledge of new ideas.We have no copies of her book, (21)       we know that she wrote several important mathematical works. Hypatia was also interested in technology and (22)       several scientific tools to help with her work. At the (23)       , many rulers were afraid of science, and (24)        connected with it was in danger. One day in March 415, Hypatia (25)           attacked in the street and killed.Điền vào ô 18

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.5 K lượt xem 5 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 3)

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.Rain forests cover less than six percent of the earth’s area, but they have 100,000 kinds of all the kinds of plants on the earth. Three-fourths of known kinds of plants and animals call the rain forest their home. Twenty percent of our different kinds of medicine comes from rain forests. The glues on an envelope and in shoes come from tropical plants. Rain forests provide materials for hundreds of other products.Rain forests are also very important to the world’s climate. The Amazon rain forest alone receives about thirty to forty percent of the total rainfall on the earth and products about the same percentage of the world oxygen. Some scientists believe that the decreasing size of rain forests will affect the climate on the earth, making it uncomfortable or even dangerous for life.Saving rain forests is an international problem. One country, or even a few countries, cannot solve the problem alone. The nations of the world must work together to find a solution before it is too late.How many known kinds of plants and animals call the rain forests their home?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1 K lượt xem 5 năm trước
Bài tập kết hợp thủy phân este và đốt cháy

Hỗn hợp E gồm hai este đơn chức, là đồng phân cấu tạo và đều chứa vòng benzen. Đốt cháy hoàn toàn m gam E cần vừa đủ 8,064 lít khí O2 (đktc), thu được 14,08 gam CO2 và 2,88 gam H2O. Đun nóng m gam E với dung dịch NaOH (dư) thì có tối đa 2,40 gam NaOH phản ứng, thu được dung dịch T chứa 5,32 gam ba muối và a gam ancol. Giá trị của a là

Hóa học Tốt nghiệp THPT
Xem chi tiết 448 lượt xem 5 năm trước
KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P12)

Joanne is criticising Alex for taking a late flight. Choose the most suitable response to fill in the blank in the following exchange.       Joanne: “You should have flown with the earlier flight!”              Alex: “___________________”

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 2.2 K lượt xem 5 năm trước
Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P12)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word for each of the blanks.THE FIRST WOMAN SCIENTISTHypatia was born in Alexandria, in Egypt, in 370 A.D. For many centuries, she was (16)          only   woman scientist to have a place in the history books.Hypatia's father was director of Alexandria University, and he (17)             sure his daughter had the best education available. This was unusual, as most women then had few (18)           to study.After studying in Athens and Rome, Hypatia returned to Alexandria (19)       she began teaching mathematics. She soon became famous (20)           her knowledge of new ideas.We have no copies of her book, (21)       we know that she wrote several important mathematical works. Hypatia was also interested in technology and (22)       several scientific tools to help with her work. At the (23)       , many rulers were afraid of science, and (24)        connected with it was in danger. One day in March 415, Hypatia (25)           attacked in the street and killed.Điền vào ô 17

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 730 lượt xem 5 năm trước
Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P12)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word for each of the blanks.THE FIRST WOMAN SCIENTISTHypatia was born in Alexandria, in Egypt, in 370 A.D. For many centuries, she was (16)          only   woman scientist to have a place in the history books.Hypatia's father was director of Alexandria University, and he (17)             sure his daughter had the best education available. This was unusual, as most women then had few (18)           to study.After studying in Athens and Rome, Hypatia returned to Alexandria (19)       she began teaching mathematics. She soon became famous (20)           her knowledge of new ideas.We have no copies of her book, (21)       we know that she wrote several important mathematical works. Hypatia was also interested in technology and (22)       several scientific tools to help with her work. At the (23)       , many rulers were afraid of science, and (24)        connected with it was in danger. One day in March 415, Hypatia (25)           attacked in the street and killed.Điền vào ô 16

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.1 K lượt xem 5 năm trước
30 đề thi thử đề thi thử THPTQG môn Tiếng Anh có lời giải chi tiết (Đề số 26)

I'm so hungry. Let’s go and get__________to eat

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 2.2 K lượt xem 7 tháng trước
Đề luyện thi THPT quốc gia môn tiếng anh có lời giải (Đề số 04)

Read the passage and choose the best option to complete each blank.Any change in one part of an ecosystem can cause changes in other parts. Droughts, storms and fires can change ecosystems. Some changes ____(46)___ ecosystems. If there is too little rainfall, plants will not have enough water to live. If a kind of plant dies off, the animals____(47)___feed on it may also die or move away. Some changes are good for ecosystems. Some pine forests need fires for the pine trees to reproduce. The seeds are sealed inside pinecones. Heat from a forest fire melts the seal and lets the seeds ____(48)___. Polluting the air, soil, and water can harm ecosystems. Building dams on rivers for electric power and irrigation can harm ecosystems ____(49)___ the rivers. Bulldozing wetlands and cutting down forests destroy ecosystems. Ecologists are working with companies and governments to find better ways of ___(50)____ fish, cutting down trees, and building dams. They are looking for ways to get food, lumber, and other products for people without causing harm to ecosystemsĐiền ô số 49

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 231 lượt xem 5 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 3)

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.Rain forests cover less than six percent of the earth’s area, but they have 100,000 kinds of all the kinds of plants on the earth. Three-fourths of known kinds of plants and animals call the rain forest their home. Twenty percent of our different kinds of medicine comes from rain forests. The glues on an envelope and in shoes come from tropical plants. Rain forests provide materials for hundreds of other products.Rain forests are also very important to the world’s climate. The Amazon rain forest alone receives about thirty to forty percent of the total rainfall on the earth and products about the same percentage of the world oxygen. Some scientists believe that the decreasing size of rain forests will affect the climate on the earth, making it uncomfortable or even dangerous for life.Saving rain forests is an international problem. One country, or even a few countries, cannot solve the problem alone. The nations of the world must work together to find a solution before it is too late.What percent of the earth’s area do rain forests cover?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 2.2 K lượt xem 5 năm trước
Đề luyện thi THPT Quốc Gia - Năm 2020 Môn thi: TIẾNG ANH (Đề số 3)

Read the following text then answer the questions that followed by circling its corresponding letter marked A, B, C or D from 43 to 50. Since water is the basis of life, composing the greater part of the tissues of all living things, the crucial problem of desert animals is to survive in a world where sources of flowing water are rare. And since man’s inexorable necessity is to absorb large quantities of water at frequent intervals, he can scarcely comprehend that many creatures of the desert pass their entire lives without a single drop. Uncompromising as it is, the desert has not a limited life but only those forms unable to withstand its desiccating effects. No moist skinned, water-loving animals can exist there. Few large animals are found. The giants of the North American desert are the deer, the coyote, and the bobcat. Since desert country is open, it holds more swift-footed running and leaping creatures than the tangled forest. Its population is largely nocturnal, silent, filled with reticence, and ruled by stealth. Yet they are not emaciated. Having adapted to their austere environment, they are as healthy as animals anywhere else in the world. The secret of their adjustment lies in the combination of behavior and physiology. None could survive, like mad dogs and Englishmen, if they went out in the midday sun, many would die in a matter of minutes. So most of them pass the burning hours asleep in cool, humid burrows underneath the ground, emerging to hunt only by night. The surface of the sun-baked desert averages around 150 degrees, but 18 inches down the temperature is only 60 degrees.The title for this passage could be _______.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 488 lượt xem 5 năm trước
KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P12)

Family_________later took on a much greater significance in his life

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.1 K lượt xem 4 năm trước
BÀI TẬP LÝ THUYẾT

Khi điện phân hỗn hợp dung dịch NaCl và CuSO4, nếu dung dịch sau khi điện phân hoà tan được NaHCO3 thì sẽ xảy trường hợp nào sau đây:

Hóa học Lớp 12
Xem chi tiết 8.2 K lượt xem 5 năm trước
Đề luyện thi THPT quốc gia môn tiếng anh có lời giải (Đề số 04)

Read the passage and choose the best option to complete each blank.Any change in one part of an ecosystem can cause changes in other parts. Droughts, storms and fires can change ecosystems. Some changes ____(46)___ ecosystems. If there is too little rainfall, plants will not have enough water to live. If a kind of plant dies off, the animals____(47)___feed on it may also die or move away. Some changes are good for ecosystems. Some pine forests need fires for the pine trees to reproduce. The seeds are sealed inside pinecones. Heat from a forest fire melts the seal and lets the seeds ____(48)___. Polluting the air, soil, and water can harm ecosystems. Building dams on rivers for electric power and irrigation can harm ecosystems ____(49)___ the rivers. Bulldozing wetlands and cutting down forests destroy ecosystems. Ecologists are working with companies and governments to find better ways of ___(50)____ fish, cutting down trees, and building dams. They are looking for ways to get food, lumber, and other products for people without causing harm to ecosystemsĐiền ô số 48

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 253 lượt xem 5 năm trước
30 đề thi thử đề thi thử THPTQG môn Tiếng Anh có lời giải chi tiết (Đề số 26)

Mrs. Brown was the first owner__________ dog                     won three prizes in the same show.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 710 lượt xem 5 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 3)

Mark the letter A, B, C or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.The agreement ended six-month negotiation. It was signed yesterday.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.8 K lượt xem 5 năm trước
BÀI TẬP LÝ THUYẾT

Chất nào sau đây được dùng để thu gom thủy ngân rơi vãi

Hóa học Lớp 12
Xem chi tiết 4.5 K lượt xem 5 năm trước
Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P12)

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction.It is noisy enough (A) in this room, so (B) I would (C) rather you stop (D) shouting like that

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 838 lượt xem 5 năm trước
Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 9)

Cho hỗn hợp khí X gồm HCHO, C2H2 và H2 đi qua ống sứ đựng bột Ni nung nóng. Sau một thời gian thu đuợc hỗn hợp Y (gồm khí và hơi). Đốt cháy hoàn toàn Y cần dùng vừa đủ 0,25 mol O2, sinh ra 0,15 mol CO2 và 4,50 gam H2O. Phần trăm khối luợng của C2H2 trong X là

Hóa học Tốt nghiệp THPT
Xem chi tiết 261 lượt xem 5 năm trước
Bài tập kết hợp thủy phân este và đốt cháy

Thủy phân hoàn toàn m1 gam este X mạch hở bằng dung dịch NaOH dư, thu được m2 gam ancol Y (không có khả năng phản ứng với Cu(OH)2) và 15 gam hỗn hợp muối của hai axit cacboxylic đơn chức. Đốt cháy hoàn toàn m2 gam Y bằng oxi dư, thu được 0,3 mol CO2 và 0,4 mol H2O. Giá trị của m1 là 

Hóa học Tốt nghiệp THPT
Xem chi tiết 291 lượt xem 5 năm trước
Đề luyện thi THPT Quốc Gia - Năm 2020 Môn thi: TIẾNG ANH (Đề số 3)

Read the following text then answer the questions that followed by circling its corresponding letter marked A, B, C or D from 38 to 42. Sometimes you know things about people the first time you see them, for example, that you want to be friends with them or that you don’t trust them. But perhaps this kind of intuition isn’t as hard to explain as it may seem. For instance, people give out their body language signals all the time. The way you hold your body, head and arms tells people about your mood. If you hold your arms tightly at your sides, or fold them across your chest, people will generally feel that you are being defensive. Holding your head to one side shows interest in the other, while an easy, open posture indicates that you are self-confident. All this affects the way you feel about someone. Also, a stranger may remind you of a meeting with someone. This may be because of something as simple as the fact that he or she is physically similar to someone who treated you well or badly. Your feelings about a stranger could be influenced by a smell in the air that brings to mind a place where you were happy as a child. Since even a single word can bring back a memory such as that, you may never realize it is happening.Intuition described in the passage can be explained by means of __________.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 2.9 K lượt xem 5 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 3)

Mark the letter A, B, C or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.We had no time. Thus, we didn’t visit the museum

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 3.7 K lượt xem 5 năm trước
BÀI TẬP LÝ THUYẾT

Kim loại tác dụng mạnh với H2O ở điều kiện thường là:

Hóa học Lớp 12
Xem chi tiết 1.9 K lượt xem 5 năm trước
Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P12)

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction.Dogs that (A) are trained (B) to lead the (C) blind must be loyalty,(D) intelligent and calm.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 613 lượt xem 5 năm trước
30 đề thi thử đề thi thử THPTQG môn Tiếng Anh có lời giải chi tiết (Đề số 26)

In some countries, many old-aged parents like to live in a nursing home. They want toindependent lives.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 803 lượt xem 5 năm trước
Đề luyện thi THPT quốc gia môn tiếng anh có lời giải (Đề số 04)

Read the passage and choose the best option to complete each blank.Any change in one part of an ecosystem can cause changes in other parts. Droughts, storms and fires can change ecosystems. Some changes ____(46)___ ecosystems. If there is too little rainfall, plants will not have enough water to live. If a kind of plant dies off, the animals____(47)___feed on it may also die or move away. Some changes are good for ecosystems. Some pine forests need fires for the pine trees to reproduce. The seeds are sealed inside pinecones. Heat from a forest fire melts the seal and lets the seeds ____(48)___. Polluting the air, soil, and water can harm ecosystems. Building dams on rivers for electric power and irrigation can harm ecosystems ____(49)___ the rivers. Bulldozing wetlands and cutting down forests destroy ecosystems. Ecologists are working with companies and governments to find better ways of ___(50)____ fish, cutting down trees, and building dams. They are looking for ways to get food, lumber, and other products for people without causing harm to ecosystemsĐiền ô số 47

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 268 lượt xem 5 năm trước
BÀI TẬP LÝ THUYẾT

Thực hiện các thí nhiệm sau:(1)   Đốt cháy bột sắt trong hơi brom.(2)   Cho bột sắt vào dung dịch H2SO4 loãng.(3)   Cho bột sắt vào dung dịch AgNO3 dư.(4)   Cho bột sắt vào dung dịch HNO3 dư.(5)   Cho bột sắt vào dung dịch HCl loãng dư.Số thí nghiệm thu được muối Fe3+  là.

Hóa học Lớp 12
Xem chi tiết 1.3 K lượt xem 5 năm trước
KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P12)

The visitors were complaining______in the rain.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 417 lượt xem 4 năm trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 3)

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.Choosing a career may be one of the hardest jobs you ever have, and it must be done with care. View a career as an opportunity to do something you love, not simply as a way to earn a living. Investing the time and effort to thoroughly explore your options can mean the difference between finding a stimulating and rewarding career and move from job to unsatisfying job in an attempt to find the right one. Work influences virtually every aspect of your life, from your choice of friends to where you live. Here are just a few of the factors to consider.Deciding what matters most to you is essential to making the right decision. You may want to begin by assessing your likes, dislikes, strengths, and weaknesses. Think about the classes, hobbies, and surroundings that you find most appealing. Ask yourself questions, such as “Would you like to travel? Do you want to work with children? Are you more suited to solitary or cooperative work?” There are no right or wrong answers; only you know what is important to you. Determine which job features you require, which ones you would prefer, and which ones you cannot accept. Then rank them in order of importance to you.The setting of the job is one factor to take into account. You may not want to sit at a desk all day. If not, there are diversity occupation – building inspector, supervisor, real estate agent – that involve a great deal of time away from the office. Geographical location may be a concern, and employment in some fields is concentrated in certain regions. Advertising job can generally be found only in large cities. On the other hand, many industries such as hospitality, law education, and retail sales are found in all regions of the country. If a high salary is important to you, do not judge a career by its starting wages. Many jobs, such as insurance sales, offers relatively low starting salaries; however, pay substantially increases along with your experience, additional training, promotions and commission.Don’t rule out any occupation without learning more about it. Some industries evoke positive or negative associations. The traveling life of a flight attendant appears glamorous, while that of a plumber does not. Remember that many jobs are not what they appear to be at first, and may have merits or demerits that are less obvious. Flight attendants must work long, grueling hours without sleeps, whereas plumbers can be as highly paid as some doctors.Another point to consider is that as you mature, you will likely develop new interests and skills that may point the way to new opportunities. The choice you make today need not be your final one.According to the passage, which of the following is true?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 614 lượt xem 5 năm trước
Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P12)

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction.She asked (A) why did Mathew look (B) so embarrassed (C) when he saw (D) Carole.

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1 K lượt xem 5 năm trước
BÀI TẬP LÝ THUYẾT

Thực hiện các thí nghiệm sau:(1)    Nung hỗn hợp Fe và KNO3 trong khí trơ.(2)    Dẫn khí CO qua bột CuO đun nóng.(3)    Đốt dây Mg trong bình kín chứa đầy SO2.(4)    Cho dung dịch C2H5OH vào CrO3.(5)    Cho Fe vào dung dịch CuSO4 và H2SO4 loãng(6)    Nung nóng dung dịch bão hòa NH4Cl và NaNO2(7)    Điện phân CaCl2 nóng chảy(5)    Nung Ag2S trong không khíKhi các phản ứng xảy ra hoàn toàn, số thí nghiệm có thể thu được chất khí là:

Hóa học Lớp 12
Xem chi tiết 648 lượt xem 5 năm trước
Đề luyện thi THPT quốc gia môn tiếng anh có lời giải (Đề số 04)

Read the passage and choose the best option to complete each blank.Any change in one part of an ecosystem can cause changes in other parts. Droughts, storms and fires can change ecosystems. Some changes ____(46)___ ecosystems. If there is too little rainfall, plants will not have enough water to live. If a kind of plant dies off, the animals____(47)___feed on it may also die or move away. Some changes are good for ecosystems. Some pine forests need fires for the pine trees to reproduce. The seeds are sealed inside pinecones. Heat from a forest fire melts the seal and lets the seeds ____(48)___. Polluting the air, soil, and water can harm ecosystems. Building dams on rivers for electric power and irrigation can harm ecosystems ____(49)___ the rivers. Bulldozing wetlands and cutting down forests destroy ecosystems. Ecologists are working with companies and governments to find better ways of ___(50)____ fish, cutting down trees, and building dams. They are looking for ways to get food, lumber, and other products for people without causing harm to ecosystemsĐiền ô số 46

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.1 K lượt xem 5 năm trước
Đề luyện thi THPT Quốc Gia - Năm 2020 Môn thi: TIẾNG ANH (Đề số 3)

Read the following text then answer the questions that followed by circling its corresponding letter marked A, B, C or D from 38 to 42. Sometimes you know things about people the first time you see them, for example, that you want to be friends with them or that you don’t trust them. But perhaps this kind of intuition isn’t as hard to explain as it may seem. For instance, people give out their body language signals all the time. The way you hold your body, head and arms tells people about your mood. If you hold your arms tightly at your sides, or fold them across your chest, people will generally feel that you are being defensive. Holding your head to one side shows interest in the other, while an easy, open posture indicates that you are self-confident. All this affects the way you feel about someone. Also, a stranger may remind you of a meeting with someone. This may be because of something as simple as the fact that he or she is physically similar to someone who treated you well or badly. Your feelings about a stranger could be influenced by a smell in the air that brings to mind a place where you were happy as a child. Since even a single word can bring back a memory such as that, you may never realize it is happening.What does the second paragraph discuss?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.8 K lượt xem 5 năm trước
BÀI TẬP LÝ THUYẾT

Cho hỗn hợp bột rắn gồm FeO, CuO, AgNO3, K2Cr2O7. Trộn thêm lượng dư bột Al và nung hỗn hợp trên ở nhiệt độ cao đến khối lượng không đổi được hỗn hợp rắn A. Cho A vào ống nghiệm B chứa lượng dư dung dịch HCI đặc, đun nóng nhẹ và khuấy đều để mọi phản ứng xảy ra hoàn toàn. Tiếp tục thêm từ từ đến dư dung dịch NaOH vào ống nghiệm B, khuấy đều để mọi phản ứng xảy ra hoàn toàn. Sau phản ứng, hỗn hợp rắn thu được trong ống nghiệm B chứa tối đa bao nhiêu chất?

Hóa học Lớp 12
Xem chi tiết 1.7 K lượt xem 5 năm trước
Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P12)

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction. Not until (A) I was on my way (B) to the airport that I realized (C) I had left my passport at home.(D)

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 630 lượt xem 11 tháng trước
Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 3)

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.Choosing a career may be one of the hardest jobs you ever have, and it must be done with care. View a career as an opportunity to do something you love, not simply as a way to earn a living. Investing the time and effort to thoroughly explore your options can mean the difference between finding a stimulating and rewarding career and move from job to unsatisfying job in an attempt to find the right one. Work influences virtually every aspect of your life, from your choice of friends to where you live. Here are just a few of the factors to consider.Deciding what matters most to you is essential to making the right decision. You may want to begin by assessing your likes, dislikes, strengths, and weaknesses. Think about the classes, hobbies, and surroundings that you find most appealing. Ask yourself questions, such as “Would you like to travel? Do you want to work with children? Are you more suited to solitary or cooperative work?” There are no right or wrong answers; only you know what is important to you. Determine which job features you require, which ones you would prefer, and which ones you cannot accept. Then rank them in order of importance to you.The setting of the job is one factor to take into account. You may not want to sit at a desk all day. If not, there are diversity occupation – building inspector, supervisor, real estate agent – that involve a great deal of time away from the office. Geographical location may be a concern, and employment in some fields is concentrated in certain regions. Advertising job can generally be found only in large cities. On the other hand, many industries such as hospitality, law education, and retail sales are found in all regions of the country. If a high salary is important to you, do not judge a career by its starting wages. Many jobs, such as insurance sales, offers relatively low starting salaries; however, pay substantially increases along with your experience, additional training, promotions and commission.Don’t rule out any occupation without learning more about it. Some industries evoke positive or negative associations. The traveling life of a flight attendant appears glamorous, while that of a plumber does not. Remember that many jobs are not what they appear to be at first, and may have merits or demerits that are less obvious. Flight attendants must work long, grueling hours without sleeps, whereas plumbers can be as highly paid as some doctors.Another point to consider is that as you mature, you will likely develop new interests and skills that may point the way to new opportunities. The choice you make today need not be your final one.Why does the author mention “long, grueling hours without sleeps” in paragraph 4? 

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 340 lượt xem 5 năm trước
Bài tập kết hợp thủy phân este và đốt cháy

Hợp chất hữu cơ Y mạch hở, có công thức phân tử trùng với công thức đơn giản nhất. Đốt cháy hoàn toàn m gam Y cần vừa đủ 3,36 lít khí O2 (đktc), thu được 7,92 gam CO2 và 1,62 gam H2O. Đun nóng m gam Y với dung dịch NaOH dư, có tối đa 2,4 gam NaOH phản ứng, thu được sản phẩm gồm etylen glicol và muối của một axit cacboxylic Z. Phát biểu nào sau đây đúng?

Hóa học Tốt nghiệp THPT
Xem chi tiết 1.5 K lượt xem 5 năm trước
CÔNG TY TNHH ĐẦU TƯ VÀ DỊCH VỤ GIÁO DỤC VIETJACK
Giấy chứng nhận ĐKKD số: 0108307822 do Sở KH & ĐT TP Hà Nội cấp lần đầu ngày 04/06/2018
© 2017 Vietjack37. All Rights Reserved.
zalo Nhắn tin Zalo Hỏi bài tập

Đăng ký

Bạn đã có tài khoản?