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Tổng hợp đề thi Tiếng Anh có lời giải (Đề số 12)

She  isn’t________well with the new manager

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Ôn tập Halogen, Ancol, Phenol cực hay có lời giải

Tiến hành thí nghiệm tổng hợp và tách chất hữu cơ X theo các bước sau:- Bước 1: cho 16,5 ml C2H5OH và 7,5 ml axit H2SO4 đặc vào bình cầu ba cổ. Lắp nhiệt kế, phễu nhỏ giọt chứa 15 ml etanol và ống sinh hàn, bình eclen như hình vẽ.- Bước 2: Đun nóng bình phản ứng đến 140oC, nhỏ từng phần C2H5OH trong phễu nhỏ giọt xuống. Sau khi cho hết C2H5OH, đun nóng bình thêm 5 phút.- Bước 3: Rửa và tách chất lỏng ngưng tụ ở bình eclen lần lượt với 10 ml dung dịch NaOH 5% và 10 ml dung dịch CaCl2 50% trong phễu chiết.- Bước 4: Cho phần chất lỏng chứa nhiều X thu được sau bước 3 vào bình đựng CaCl2 khan. Sau 5 giờ, lọc lấy lớp chất lỏng và chưng cất phân đoạn trên bếp cách thủy ở 35 – 38oC, thu được chất X tương đối tinh khiết.Cho các phát biểu sau:(a) Sau bước 1, chất lỏng trong bình cầu phân thành hai lớp.(b) Sau bước 2, thu được chất lỏng trong bình eclen có hai lớp.(c) Mục đích dùng dung dịch CaCl2 50% ở bước 3 để giảm độ tan của X trong nước và đẩy X lên trên.(d) Mục đích sử dụng CaCl2 khan ở bước 4 để tạo kết tủa với H2SO4. Số phát biểu đúng là

Hóa học Lớp 11
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Tổng hợp đề thi Tiếng Anh có lời giải (Đề số 12)

Without  my parents' support, ________my overseas study

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P4)

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.Legend has it that sometime toward the end of the Civil war (1861 – 1865) a government train carrying oxen travelling through the northern plains of eastern Wyoming was caught in a snowstorm and had to be abandoned. The diver returned the next spring to see what had become of his cargo. Instead of the skeletons he had expected to find, he saw his oxen, living, fat and healthy. How had they survived?The answer lay in the resource that unknowing American lands trampled underfoot in their haste to cross the “Great American Desert” to reach lands that sometimes proved barren. In the eastern parts of the United States, the preferred grass for forage was a cultivated plant. It grew well with enough rain, then when cut and stored it would cure and become nourishing hay for winter feed. But in the dry grazing lands of the west that familiar bluejoint grass was often killed by drought. To cattle out there seemed risky or even hopeless.Who could imagine a fairy-tail grass that required no rain and somehow made it possible for cattle to feed themselves all winter? But the surprising western wild grasses did just that. They had wonderfully convenient features that made them superior to the cultivated eastern grasses. Variously known as buffalo grass, grama grass, or mesquite grass, not only were they immune to drought; but they were actually preserved by the lack of summer and autumn rains. They were not juicy like the cultivated eastern grasses, but had short, hard stems. And they did not need to be cured in a barn, but dried right where they grew on the ground. When they dried in this way, they remained naturally sweet and nourishing through the winter. Cattle left outdoors to fend for themselves thrived on this hay. And the cattle themselves helped plant the fresh grass year after year for they trampled the natural seeds firmly into the soil to be watered by the melting snows of winter and the occasional rains of spring. The dry summer air cured them much as storing in a barn cured the cultivated grasses. The word “barren” in paragraph 2 is closest in meaning to _________.

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp bài tập Hóa vô cơ hay và khó (P2)

Điện phân điện cực trơ màng ngăn xốp, dung dịch X chứa a gam Cu(NO3)2 và b gam NaCl đến khi có khí thoát ra ở cả 2 điện cực thì dừng lại, thu được dung dịch Y và 0,51 mol khí Z. Dung dịch Y hòa tan tối đa 12,6 gam Fe giải phóng NO (sản phẩm khử duy nhất) và dung dịch T. Dung dịch T cho kết tủa với dung dịch AgNO3. Tổng giá trị của (a + b) là

Hóa học Lớp 12
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208 Bài tập Nito - photpho cực hay có đáp án (P4)

Cho phương trình: H3PO4 3H++PO43-. Khi thêm HCl vào:

Hóa học Lớp 11
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Ôn luyện hóa hữu cơ 12 cực hay có lời giải (Đề số 06)

Thủy phân 60,6 gam Gly-Gly-Gly-Gly-Gly thì thu được m gam Gly-Gly-Gly; 13,2 gam Gly-Gly và 37,5 gam glyxin. Giá trị của m là

Hóa học Lớp 12
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30 đề luyện thi Đại Học môn Tiếng Anh cực hay có lời giải (Đề số 28)

Mark the letter A, B, C, or D on your answer sheet to show the underlinedpart that needs correctionDaisy has such many things to do that she has to no time to go out.

Tiếng Anh Tốt nghiệp THPT
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KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P4)

 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.Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.The word “innate” in bold is closest in meaning to______   

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P4)

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.Legend has it that sometime toward the end of the Civil war (1861 – 1865) a government train carrying oxen travelling through the northern plains of eastern Wyoming was caught in a snowstorm and had to be abandoned. The diver returned the next spring to see what had become of his cargo. Instead of the skeletons he had expected to find, he saw his oxen, living, fat and healthy. How had they survived?The answer lay in the resource that unknowing American lands trampled underfoot in their haste to cross the “Great American Desert” to reach lands that sometimes proved barren. In the eastern parts of the United States, the preferred grass for forage was a cultivated plant. It grew well with enough rain, then when cut and stored it would cure and become nourishing hay for winter feed. But in the dry grazing lands of the west that familiar bluejoint grass was often killed by drought. To cattle out there seemed risky or even hopeless.Who could imagine a fairy-tail grass that required no rain and somehow made it possible for cattle to feed themselves all winter? But the surprising western wild grasses did just that. They had wonderfully convenient features that made them superior to the cultivated eastern grasses. Variously known as buffalo grass, grama grass, or mesquite grass, not only were they immune to drought; but they were actually preserved by the lack of summer and autumn rains. They were not juicy like the cultivated eastern grasses, but had short, hard stems. And they did not need to be cured in a barn, but dried right where they grew on the ground. When they dried in this way, they remained naturally sweet and nourishing through the winter. Cattle left outdoors to fend for themselves thrived on this hay. And the cattle themselves helped plant the fresh grass year after year for they trampled the natural seeds firmly into the soil to be watered by the melting snows of winter and the occasional rains of spring. The dry summer air cured them much as storing in a barn cured the cultivated grasses. What can be inferred about the “Great American Desert” mentioned in paragraph 2?

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp bài tập Hóa vô cơ hay và khó (P2)

Hòa tan hết m gam hỗn hợp X gồm Na, Na2O, K, K2O, Ba và BaO (oxi chiếm 8,75% về khối lượng) vào nước, thu được 400 ml dung dịch Y và 1,568 lít H2 (đktc). Trộn 200 ml dung dịch Y với 200 ml dung dịch hỗn hợp gồm HCl 0,2M và H2SO4 0,15M, thu được 400 ml dung dịch có pH = 13. Các phản ứng xảy ra hoàn toàn. Giá trị m gần giá trị nào nhất sau đây?

Hóa học Lớp 12
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Ôn luyện hóa hữu cơ 12 cực hay có lời giải (Đề số 09)

Thủy phân hoàn toàn 0,05 mol este X của 1 axit đa chức với 1 ancol đơn chức cần 5,6 gam KOH. Mặt khác, khi thủy phân 5,475 gam este đó thì cần 4,2 gam KOH và thu được 6,225 gam muối. Công thức cấu tạo của este là

Hóa học Lớp 12
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Ôn tập Halogen, Ancol, Phenol cực hay có lời giải

Chia 20,8 gam hỗn hợp gồm hai anđehit đơn chức là đồng đẳng kế tiếp thành hai phần bằng nhau. Phần một tác dụng hoàn toàn với lượng dư dung dịch AgNO3 trong NH3 đun nóng, thu được 108 gam Ag. Phần hai tác dụng hoàn toàn với H2 dư (xúc tác Ni, t°), thu được hỗn hợp X gồm hai ancol Y và Z (My<MZ). Đun nóng X với H2SO4 đặc ở 140°C, thu được 4,52 gam hỗn hợp ba ete. Biết hiệu suất phản ứng tạo ete của Y bằng 50%. Hiệu suất phản ứng tạo ete của Z bằng

Hóa học Lớp 11
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Ôn luyện hóa hữu cơ 12 cực hay có lời giải (Đề số 06)

Khi nghiên cứu tính chất hoá học của este người ta tiến hành làm thí nghiệm như sau: Cho vào 2 ống nghiệm mỗi ống 2 ml etyl axetat, sau đó thêm vào ống thứ nhất 1 ml dd H2SO4 20%, vào ống thứ hai 1 ml dd NaOH 30%. Sau đó lắc đều cả 2 ống nghiệm, lắp ống sinh hàn đồng thời đun cách thuỷ trong khoảng 5 phút. Hiện tượng trong 2 ống nghiệm là:

Hóa học Lớp 12
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Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P4)

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.Legend has it that sometime toward the end of the Civil war (1861 – 1865) a government train carrying oxen travelling through the northern plains of eastern Wyoming was caught in a snowstorm and had to be abandoned. The diver returned the next spring to see what had become of his cargo. Instead of the skeletons he had expected to find, he saw his oxen, living, fat and healthy. How had they survived?The answer lay in the resource that unknowing American lands trampled underfoot in their haste to cross the “Great American Desert” to reach lands that sometimes proved barren. In the eastern parts of the United States, the preferred grass for forage was a cultivated plant. It grew well with enough rain, then when cut and stored it would cure and become nourishing hay for winter feed. But in the dry grazing lands of the west that familiar bluejoint grass was often killed by drought. To cattle out there seemed risky or even hopeless.Who could imagine a fairy-tail grass that required no rain and somehow made it possible for cattle to feed themselves all winter? But the surprising western wild grasses did just that. They had wonderfully convenient features that made them superior to the cultivated eastern grasses. Variously known as buffalo grass, grama grass, or mesquite grass, not only were they immune to drought; but they were actually preserved by the lack of summer and autumn rains. They were not juicy like the cultivated eastern grasses, but had short, hard stems. And they did not need to be cured in a barn, but dried right where they grew on the ground. When they dried in this way, they remained naturally sweet and nourishing through the winter. Cattle left outdoors to fend for themselves thrived on this hay. And the cattle themselves helped plant the fresh grass year after year for they trampled the natural seeds firmly into the soil to be watered by the melting snows of winter and the occasional rains of spring. The dry summer air cured them much as storing in a barn cured the cultivated grasses. The word “they” in paragraph 1 refers to _________.

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp bài tập Hóa vô cơ hay và khó (P2)

Hỗn hợp X gồm Cu2O, FeO, M (kim loại M có hóa trị không đổi), trong X số mol của ion O2- gấp 2 lần số mol M. Hòa tan 38,55 gam X trong dung dịch HNO3 loãng dư thấy có 1,5 mol HNO3 phản ứng, sau phản ứng thu được 118,35 gam hỗn hợp muối và 2,24 lít NO (đktc). Tính phần trăm khối lượng của M trong X?

Hóa học Lớp 12
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KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P4)

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.Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.Which of the following is NOT given as an advantage of using biological agents over chemical herbicides?

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P4)

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.Legend has it that sometime toward the end of the Civil war (1861 – 1865) a government train carrying oxen travelling through the northern plains of eastern Wyoming was caught in a snowstorm and had to be abandoned. The diver returned the next spring to see what had become of his cargo. Instead of the skeletons he had expected to find, he saw his oxen, living, fat and healthy. How had they survived?The answer lay in the resource that unknowing American lands trampled underfoot in their haste to cross the “Great American Desert” to reach lands that sometimes proved barren. In the eastern parts of the United States, the preferred grass for forage was a cultivated plant. It grew well with enough rain, then when cut and stored it would cure and become nourishing hay for winter feed. But in the dry grazing lands of the west that familiar bluejoint grass was often killed by drought. To cattle out there seemed risky or even hopeless.Who could imagine a fairy-tail grass that required no rain and somehow made it possible for cattle to feed themselves all winter? But the surprising western wild grasses did just that. They had wonderfully convenient features that made them superior to the cultivated eastern grasses. Variously known as buffalo grass, grama grass, or mesquite grass, not only were they immune to drought; but they were actually preserved by the lack of summer and autumn rains. They were not juicy like the cultivated eastern grasses, but had short, hard stems. And they did not need to be cured in a barn, but dried right where they grew on the ground. When they dried in this way, they remained naturally sweet and nourishing through the winter. Cattle left outdoors to fend for themselves thrived on this hay. And the cattle themselves helped plant the fresh grass year after year for they trampled the natural seeds firmly into the soil to be watered by the melting snows of winter and the occasional rains of spring. The dry summer air cured them much as storing in a barn cured the cultivated grasses. What can be inferred by the phrase “legend has it” in paragraph 1?

Tiếng Anh Tốt nghiệp THPT
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30 đề luyện thi Đại Học môn Tiếng Anh cực hay có lời giải (Đề số 28)

Mark the letter A, B, C, or D on your answer sheet to show the underlinedpart that needs correctionUnlike many writings of her time, she was not preoccupied with morality.

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp bài tập Hóa vô cơ hay và khó (P2)

Dung dịch X gồm CuCl2 0,2M; FeCl2 0,3M; FeCl3 0,3M. Cho m gam bột Mg vào 100 ml dung dịch X khuấy đều đến khi phản ứng kết thúc thu được dung dịch Y. Thêm dung dịch KOH dư vào Y được kết tủa Z. Nung Z trong không khí đến khối lượng không đổi thu được 5,4 gam chất rắn T. Giá trị của m là

Hóa học Lớp 12
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Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P4)

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.Legend has it that sometime toward the end of the Civil war (1861 – 1865) a government train carrying oxen travelling through the northern plains of eastern Wyoming was caught in a snowstorm and had to be abandoned. The diver returned the next spring to see what had become of his cargo. Instead of the skeletons he had expected to find, he saw his oxen, living, fat and healthy. How had they survived?The answer lay in the resource that unknowing American lands trampled underfoot in their haste to cross the “Great American Desert” to reach lands that sometimes proved barren. In the eastern parts of the United States, the preferred grass for forage was a cultivated plant. It grew well with enough rain, then when cut and stored it would cure and become nourishing hay for winter feed. But in the dry grazing lands of the west that familiar bluejoint grass was often killed by drought. To cattle out there seemed risky or even hopeless.Who could imagine a fairy-tail grass that required no rain and somehow made it possible for cattle to feed themselves all winter? But the surprising western wild grasses did just that. They had wonderfully convenient features that made them superior to the cultivated eastern grasses. Variously known as buffalo grass, grama grass, or mesquite grass, not only were they immune to drought; but they were actually preserved by the lack of summer and autumn rains. They were not juicy like the cultivated eastern grasses, but had short, hard stems. And they did not need to be cured in a barn, but dried right where they grew on the ground. When they dried in this way, they remained naturally sweet and nourishing through the winter. Cattle left outdoors to fend for themselves thrived on this hay. And the cattle themselves helped plant the fresh grass year after year for they trampled the natural seeds firmly into the soil to be watered by the melting snows of winter and the occasional rains of spring. The dry summer air cured them much as storing in a barn cured the cultivated grasses. What does the passage mainly discuss?

Tiếng Anh Tốt nghiệp THPT
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KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P4)

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.Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.Which of the following statements about the use of chemical agents as herbicides would the author most likely agree?

Tiếng Anh Tốt nghiệp THPT
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Ôn luyện hóa hữu cơ 12 cực hay có lời giải (Đề số 06)

Đốt cháy hoàn toàn m gam este đơn chức X cần vừa đủ 20,16 lít O2, sản phẩm thu được gồm 17,92 lít CO2 và 7,2 gam H2O (các thể tích khí đo ở điều kiện tiêu chuẩn). Mặt khác, khi thuỷ phân X trong môi trường kiềm thì thu được 2 muối. Có bao nhiêu công thức cấu tạo thoả mãn tính chất của X là

Hóa học Lớp 12
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Tổng hợp bài tập Hóa vô cơ hay và khó (P2)

Đốt cháy m gam hỗn hợp Mg, Fe trong oxi một thời gian, thu được (m + 4,16) gam hỗn hợp X chứa các oxit. Hòa tan hoàn toàn hỗn hợp X bằng dung dịch HCl vừa đủ, thu được dung dịch Y chứa (3m + 1,82) gam muối. Cho AgNO3 dư vào dung dịch Y thấy tạo (9m + 4,06) gam kết tủa. Mặt khác, hòa tan hết 3,75m gam hỗn hợp X bằng dung dịch HNO3 loãng (dư), thu được dung dịch Z chứa x gam muối nitrat kim loại. Giá trị của  x là

Hóa học Lớp 12
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208 Bài tập Nito - photpho cực hay có đáp án (P4)

Dung dịch axit photphoric có chứa các ion (không kể H+ và OH-)

Hóa học Lớp 11
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30 đề luyện thi Đại Học môn Tiếng Anh cực hay có lời giải (Đề số 28)

Mark the letter A, B, C, or D on your answer sheet to show the underlinedpart that needs correctionThere are differences and simillarities between Vietnamese and American culture.

Tiếng Anh Tốt nghiệp THPT
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KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P4)

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.Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.Which of the following terms does the author define in the first paragraph?

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P4)

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 45 to 54.POLAR BEARSPolar bears are in danger of dying out. (45) _________ some other endangered animals, it’s not hunters that are the problem, it’s climate change. Since 1979, the ice cap at the Arctic Circle where the polar bears live has (46) _________ in size by about 30 percent. The temperature in the Arctic has slowly been (47) _________ and this is (48) _________ the sea ice to melt, endangering the polar bears’ home.The polar bears’ main (49) _________ of food are the different types of seal found in the Arctic. They catch them by waiting next to the air holes the seals have (50) _________in the ice. (51) _________ the bears are very strong swimmers, they could never catch seals in the water. This means that the bears (52) _________ do rely on the ice to hunt.Polar bears also need sea ice to travel. They can (53) _________ a huge territory and often swim from one part of the ice to another. They have been known to swim up to 100km, but when there is less ice, they may have to swim further and this can (54) _________ fatal to the bears. A number of bears have drowned in the last few years and scientists believe that it is because they were not able to reach more sea ice before they became too tired and couldn’t swim any further.Điền vào ô 54

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Tổng hợp bài tập Hóa vô cơ hay và khó (P2)

Hòa tan hết m gam Cu vào dung dịch gồm Fe(NO3)3 và HCl, thu được dung dịch X và khí NO. Thêm tiếp 19,2 gam Cu vào X, sau phản ứng thu được dung dịch Y chỉ chứa 2 muối trung hòa và còn lại 6,4 gam chất rắn. Cho toàn bộ Y vào dung dịch AgNO3 dư, thu được 183 gam kết tủa. Biết các phản ứng xảy ra hoàn toàn. Giá trị của m là

Hóa học Lớp 12
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Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 8)

Oxit nào dưới đây thuộc loại oxit axit?

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Ôn luyện hóa hữu cơ 12 cực hay có lời giải (Đề số 06)

Phát biểu nào sau đây không đúng?

Hóa học Lớp 12
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Tổng hợp bài tập Hóa vô cơ hay và khó (P2)

Lấy hỗn hợp X gồm Zn và 0,3 mol Cu(NO3)2 nhiệt phân một thời gian, thu được hỗn hợp rắn Y và 10,08 lít hỗn hợp khí Z gồm NO2 và O2. Y tác dụng vừa đủ với dung dịch chứa 2,3 mol HCl, thu được dung dịch T chỉ chứa các muối clorua và 2,24 lít (đktc) hỗn hợp khí E gồm 2 đơn chất không màu có tỉ khối so với H2 là 7,5. Tổng khối lượng muối trong dung dịch T có giá trị gần nhất với

Hóa học Lớp 12
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KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P4)

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.Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.The word “clog” in bold is closest in meaning to ________.

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P4)

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 45 to 54.POLAR BEARSPolar bears are in danger of dying out. (45) _________ some other endangered animals, it’s not hunters that are the problem, it’s climate change. Since 1979, the ice cap at the Arctic Circle where the polar bears live has (46) _________ in size by about 30 percent. The temperature in the Arctic has slowly been (47) _________ and this is (48) _________ the sea ice to melt, endangering the polar bears’ home.The polar bears’ main (49) _________ of food are the different types of seal found in the Arctic. They catch them by waiting next to the air holes the seals have (50) _________in the ice. (51) _________ the bears are very strong swimmers, they could never catch seals in the water. This means that the bears (52) _________ do rely on the ice to hunt.Polar bears also need sea ice to travel. They can (53) _________ a huge territory and often swim from one part of the ice to another. They have been known to swim up to 100km, but when there is less ice, they may have to swim further and this can (54) _________ fatal to the bears. A number of bears have drowned in the last few years and scientists believe that it is because they were not able to reach more sea ice before they became too tired and couldn’t swim any further.Điền vào ô 53

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P4)

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 45 to 54.POLAR BEARSPolar bears are in danger of dying out. (45) _________ some other endangered animals, it’s not hunters that are the problem, it’s climate change. Since 1979, the ice cap at the Arctic Circle where the polar bears live has (46) _________ in size by about 30 percent. The temperature in the Arctic has slowly been (47) _________ and this is (48) _________ the sea ice to melt, endangering the polar bears’ home.The polar bears’ main (49) _________ of food are the different types of seal found in the Arctic. They catch them by waiting next to the air holes the seals have (50) _________in the ice. (51) _________ the bears are very strong swimmers, they could never catch seals in the water. This means that the bears (52) _________ do rely on the ice to hunt.Polar bears also need sea ice to travel. They can (53) _________ a huge territory and often swim from one part of the ice to another. They have been known to swim up to 100km, but when there is less ice, they may have to swim further and this can (54) _________ fatal to the bears. A number of bears have drowned in the last few years and scientists believe that it is because they were not able to reach more sea ice before they became too tired and couldn’t swim any further.Điền vào ô 52

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp bài tập Hóa vô cơ hay và khó (P2)

Hỗn hợp X có khối lượng 15,44 gam gồm bột Cu và oxit sắt FexOy được chia thành hai phần bằng nhau: - Phần 1 tác dụng với dung dịch HCl dư, thu được m gam chất rắn không tan.  - Phần 2 cho tác dụng hoàn toàn với dung dịch HNO3 đặc, nóng (dư), thu được dung dịch Y và 1,904 lít khí NO2 (đktc, sản phẩm khử duy nhất). Cô cạn Y được 23,79 gam hỗn hợp chất rắn khan. Giá trị của m là 

Hóa học Lớp 12
Xem chi tiết 5.4 K lượt xem 5 năm trước
Ôn luyện hóa hữu cơ 12 cực hay có lời giải (Đề số 09)

Đun nóng 45,54 gam hỗn hợp E gồm hexapeptit X và tetrapeptit Y cần dùng 580 ml dung dịch NaOH 1M chỉ thu được dung dịch chứa muối natri của glyxin và valin. Mặt khác, đốt cháy cùng lượng E trên trong O2 vừa đủ thu được hỗn hợp CO2, H2O, N2; trong đó tổng khối lượng của CO2 và H2O là 115,18 gam. Công thức phân tử của peptit X là

Hóa học Lớp 12
Xem chi tiết 455 lượt xem 5 năm trước
Tổng hợp bài tập Hóa vô cơ hay và khó (P2)

Điện phân dung dịch X gồm x mol KCl và y mol Cu(NO3)2 (điện cực trơ, màng ngăn xốp), khi nước bắt đầu bị điện phân ở cả hai điện cực thì ngừng điện phân thu được dung dịch Y (làm quỳ tím hóa xanh), có khối lượng giảm 2,755 gam so với khối lượng dung dịch X ban đầu (giả thiết nước bay hơi không đáng kể). Trung hòa toàn bộ lượng Y bằng dung dịch HCl 1M thì cần 20 ml. Tỉ lệ x : y có giá trị gần nhất với

Hóa học Lớp 12
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Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P4)

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 45 to 54.POLAR BEARSPolar bears are in danger of dying out. (45) _________ some other endangered animals, it’s not hunters that are the problem, it’s climate change. Since 1979, the ice cap at the Arctic Circle where the polar bears live has (46) _________ in size by about 30 percent. The temperature in the Arctic has slowly been (47) _________ and this is (48) _________ the sea ice to melt, endangering the polar bears’ home.The polar bears’ main (49) _________ of food are the different types of seal found in the Arctic. They catch them by waiting next to the air holes the seals have (50) _________in the ice. (51) _________ the bears are very strong swimmers, they could never catch seals in the water. This means that the bears (52) _________ do rely on the ice to hunt.Polar bears also need sea ice to travel. They can (53) _________ a huge territory and often swim from one part of the ice to another. They have been known to swim up to 100km, but when there is less ice, they may have to swim further and this can (54) _________ fatal to the bears. A number of bears have drowned in the last few years and scientists believe that it is because they were not able to reach more sea ice before they became too tired and couldn’t swim any further.Điền vào ô 51

Tiếng Anh Tốt nghiệp THPT
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Tổng hợp đề thi thử mới nhất môn tiếng anh cực hay có lời giải (P4)

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 45 to 54.POLAR BEARSPolar bears are in danger of dying out. (45) _________ some other endangered animals, it’s not hunters that are the problem, it’s climate change. Since 1979, the ice cap at the Arctic Circle where the polar bears live has (46) _________ in size by about 30 percent. The temperature in the Arctic has slowly been (47) _________ and this is (48) _________ the sea ice to melt, endangering the polar bears’ home.The polar bears’ main (49) _________ of food are the different types of seal found in the Arctic. They catch them by waiting next to the air holes the seals have (50) _________in the ice. (51) _________ the bears are very strong swimmers, they could never catch seals in the water. This means that the bears (52) _________ do rely on the ice to hunt.Polar bears also need sea ice to travel. They can (53) _________ a huge territory and often swim from one part of the ice to another. They have been known to swim up to 100km, but when there is less ice, they may have to swim further and this can (54) _________ fatal to the bears. A number of bears have drowned in the last few years and scientists believe that it is because they were not able to reach more sea ice before they became too tired and couldn’t swim any further.Điền vào ô 50

Tiếng Anh Tốt nghiệp THPT
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30 đề luyện thi Đại Học môn Tiếng Anh cực hay có lời giải (Đề số 28)

Mark the letter A, B, C, or D on your answer sheet to show the underlinedpart that needs correctionSociety will be having to change radically to keep face with the technology available.

Tiếng Anh Tốt nghiệp THPT
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Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 8)

Tên gọi của CH3COOCH3 là:

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KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P4)

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.Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.The word “marring” in bold is closest in meaning to ________.

Tiếng Anh Tốt nghiệp THPT
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Ôn luyện hóa hữu cơ 12 cực hay có lời giải (Đề số 09)

Đốt cháy m gam hỗn hợp X gồm etyl axetat, axit acrylic và anđehit axetic rồi cho toàn bộ sản phẩm cháy hấp thụ hết vào bình đựng nước vôi trong dư thu được 45 gam kết tủa và khối lượng bình nước vôi trong tăng 27 gam. Số mol axit acrylic có trong m gam hỗn hợp X là

Hóa học Lớp 12
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Ôn luyện hóa hữu cơ 12 cực hay có lời giải (Đề số 09)

Este X no, mạch hở có 4 nguyên tử cacbon. Thủy phân X trong môi trường axit thu được ancol Y và axit Z (Y, Z chỉ chứa một loại nhóm chức duy nhất). Số công thức cấu tạo của X là

Hóa học Lớp 12
Xem chi tiết 491 lượt xem 5 năm trước
KỲ THI THỬ THPT QUỐC GIA NĂM 2019 MÔN TIẾNG ANH(P4)

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.Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.With what topic does this passage primarily deal?

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208 Bài tập Nito - photpho cực hay có đáp án (P4)

Khi đun nóng trong điều kiện không có không khí, photpho đỏ chuyển thành hơi; sau đó làm lạnh phần hơi thì thu được photpho

Hóa học Lớp 11
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Tổng hợp bài tập Hóa vô cơ hay và khó (P2)

Cho 7,76 gam hỗn hợp X gồm Fe và Cu nFe:nCu=7:6 tác dụng với dung dịch chứa 0,4 mol HNO3, thu được dung dịch Y và khí NO (sản phẩm khử duy nhất của N+5). Tiến hành điện phân dung dịch Y với điện cực trơ, cường độ dòng điện không đổi I = 9,65A trong thời gian t giây, thấy khối lượng catot tăng 4,96 gam (kim loại sinh ra bám hết vào catot). Giá trị của t là

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30 đề luyện thi Đại Học môn Tiếng Anh cực hay có lời giải (Đề số 28)

Mark the letter A, B, C, or D on your answer sheet to show the underlinedpart that needs correction.Building thousands of years ago, the ancient palace is popular with modern tourists.

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Ôn luyện hóa hữu cơ 12 cực hay có lời giải (Đề số 09)

Phát biểu nào sau đây đúng

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