công thức hóa học của phosphoric acid là H3PO4
a) nêu những điều em biết đc về phosphoric acid
b) nhóm PO4 có hóa trị bao nhiêu
a, Tham Khảo
Axit photphoric là chất tinh thể trong suốt, tồn tại dưới 2 dạng: Chất rắn tinh thể không màu (tan vô hạn trong nước hoặc cồn với cấu trúc tứ diện đều) và chất lỏng trong suốt (không màu, có vị chua). Thông thường, axit photphoric được sử dụng dưới dạng dung dịch đặc, sánh, không có màu với nồng độ 85%.
b, Nhóm \(PO_{\text{4}}\) có hóa trị là III.
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Đáp án :: Hoá trị PO4=IIIPO4=III
Giải thích các bước giải:
a)H3POA→a)H3POA→ Axit photphoric :: Chất tinh thể trong suốt, gồm 22 kiểu ::
+)+) Chất rắn tinh thể không có màu
+)+) Chất lỏng trong suốt có vị chua và cũng không có màu
b)H3PO4b)H3PO4
Gọi aa là hoá trị cần tìm của PO4PO4
Áp dụng QTHTQTHT ta có ::
3.I=1.a⇔a=3.I1=III3.I=1.a⇔a=3.I1=III
Vậy hoá trị của PO4PO4 trong CTHHCTHH H3PO4H3PO4 là IIIIII
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SGK Chân trời sáng tạo - Trang 49
25 tháng 2 2023 lúc 18:40
Viết công thức hóa học của phosphoric acid có cấu tạo từ hydrogen và nhóm phosphate. Trong phosphoric aicd, nguyên tố nào có phần trăm lớn nhất?
Gọi ct chung: \(H^I_x\left(PO_4\right)^{III}_y\)
Theo qui tắc hóa trị: `x*I=y*III -> x/y =`\(\dfrac{III}{I}\)
`-> x=3 , y=1`
`-> CTHH: H_3PO_4`
`---`
`K.L.P.T=1*3+31+16*4=98 <am``u>`
\(\%H=\dfrac{1.3.100}{98}\approx3,06\%\)
\(\%P=\dfrac{31.100}{98}\approx31,63\%\)
`%O=100% - 3,06% - 31,63%=65,31%`
`->` Nguyên tố `O` có số phần trăm lớn nhất.
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Viết phương trình phản ứng khi cho các chất sau: K2O, CaO, AL2O3, KOH, Ca(OH)2, Al2(OH)3; lần lượt tác dụng với: a) Hydrochloric acid b) Sulfuric acid c) Phosphoric acid
\(a)K_2O+2HCl\rightarrow2KCl+H_2O\\ CaO+2HCl\rightarrow CaCl_2+H_2O\\ Al_2O_3+6HCl\rightarrow2AlCl_3+3H_2O\\ KOH+HCl\rightarrow KCl+H_2O\\ Ca\left(OH\right)_2+2HCl\rightarrow CaCl_2+2H_2O\\Al\left(OH\right)_3+3HCl\rightarrow AlCl_3+3H_2O\\ b)K_2O+H_2SO_4\rightarrow K_2SO_4+H_2O\\ CaO+H_2SO_4\rightarrow CaSO_4+H_2O\\ Al_2O_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2O\\ 2KOH+H_2SO_4\rightarrow K_2SO_4+2H_2O\\ Ca\left(OH\right)_2+H_2SO_4\rightarrow CaSO_4+2H_2O\\2 Al\left(OH\right)_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+6H_2O\)
\(c)3K_2O+2H_3PO_4\rightarrow2K_3PO_4+3H_2O\\ 3CaO+2H_3PO_4\rightarrow Ca_3\left(PO_4\right)_2+3H_2O\\Al_2O_3+2H_3PO_4\rightarrow2AlPO_4+3H_2O\\ 2KOH+H_3PO_4\rightarrow K_3PO_4+2H_2O\\ 3Ca\left(OH\right)_2+2H_3PO_4\rightarrow Ca_3\left(PO_4\right)_2+6H_2O\\ Al\left(OH\right)_3+H_3PO_4\rightarrow AlPO_4+3H_2O\)
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Cần lấy bao nhiêu gam NaOH cho vào dd có chứa 5,88g acid phosphoric để thu. được 2,84g natri hidrophoshpat và 6,56g natriphosphat?
SGK Cánh diều - Trang 41
21 tháng 2 2023 lúc 19:49
Viết công thức hóa học của các chất:
a) Sodium sulfide, biết trong phân tử có 2 nguyên tử Na và 1 nguyên tử S
b) Phosphoric acid, biết trong phân tử có 3 nguyên tử H, 1 nguyên tử P và 4 nguyên tử O
III. Complete each sentence with an appropriate word. The first letter of each word is given.
1. The fish have died because the river water is heavily p________.
2. Health e________ from air pollution include lung cancer, and respiratory diseases.
3. Acid rain causes serious d________ to plants and trees.
4. If the air wasn’t dirty, Nick w________ sneeze so much.
5. The main gases that l________ to acid rain are sulfur dioxide and nitrogen dioxide.
6. There is a danger of serious contamination f...
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III. Complete each sentence with an appropriate word. The first letter of each word is given.
1. The fish have died because the river water is heavily p________.
2. Health e________ from air pollution include lung cancer, and respiratory diseases.
3. Acid rain causes serious d________ to plants and trees.
4. If the air wasn’t dirty, Nick w________ sneeze so much.
5. The main gases that l________ to acid rain are sulfur dioxide and nitrogen dioxide.
6. There is a danger of serious contamination from radioactive w________.
7. Hundreds of d________ fish were found floating in the river near the factory.
8. U________ sewage can spread disease and contaminate drinking water sources.
III. Complete each sentence with an appropriate word. The first letter of each word is given.
1. The fish have died because the river water is heavily polluted.
2. Health effects from air pollution include lung cancer, and respiratory diseases.
3. Acid rain causes serious damage to plants and trees.
4. If the air wasn’t dirty, Nick wouldn't sneeze so much.
5. The main gases that lead to acid rain are sulfur dioxide and nitrogen dioxide.
6. There is a danger of serious contamination from radioactive waste.
7. Hundreds of dead fish were found floating in the river near the factory.
8. Untreated sewage can spread disease and contaminate drinking water sources.
Read the following passage and choose A, B, C, or D to indicate the correct word or phrase that best fits each of the following blanks. Fill in the appropriate word in question 34There are many sources of pollution in our modern world. At present, the most severe sources are acid rain, car exhaust fumes and oil spills.Factory chimneys give (31)_________ smoke that contains sulfur dioxide and nitrogen oxide. These gases combine with the moisture in the atmosphere to (32)_________ sulfuric acid an...
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Read the following passage and choose A, B, C, or D to indicate the correct word or phrase that best fits each of the following blanks. Fill in the appropriate word in question 34
There are many sources of pollution in our modern world. At present, the most severe sources are acid rain, car exhaust fumes and oil spills.
Factory chimneys give (31)_________ smoke that contains sulfur dioxide and nitrogen oxide. These gases combine with the moisture in the atmosphere to (32)_________ sulfuric acid and nitric acid. When it rains, these acids dissolve in the rain and turn it acidic. Acid rain is thought to be the worst pollution problem of all. It has (33)_________ aquatic life by turning many lake into lifeless bodies of water. In these areas, there is no limestone in the rocks to neutralize the acid rain naturally. One remedy is to pump limestone into the acidic lakes. (34)_________, it is not possible to do this on a large enough scale to save all the lakes.
Car exhaust fumes contain carbon monoxide and lead which are highly poisonous. In big cities, the exhaust fumes build (35)_________ and pose a health hazard to human beings.
Pollution of the sea by oil threatens marine life. Much of the oil comes from ships that clean their fuel tanks while at sea. Offshore oil wells also discharge vast amounts of oil into the sea. Pollution of the sea can also be caused by oil spills. An oil spill may occur as a result of accidents involving oil tankers.
A. However
B. Moreover
C. So
D. Because
Read the following passage and choose A, B, C, or D to indicate the correct word or phrase that best fits each of the following blanks. Fill in the appropriate word in question 35There are many sources of pollution in our modern world. At present, the most severe sources are acid rain, car exhaust fumes and oil spills.Factory chimneys give (31)_________ smoke that contains sulfur dioxide and nitrogen oxide. These gases combine with the moisture in the atmosphere to (32)_________ sulfuric acid an...
Đọc tiếp
Read the following passage and choose A, B, C, or D to indicate the correct word or phrase that best fits each of the following blanks. Fill in the appropriate word in question 35
There are many sources of pollution in our modern world. At present, the most severe sources are acid rain, car exhaust fumes and oil spills.
Factory chimneys give (31)_________ smoke that contains sulfur dioxide and nitrogen oxide. These gases combine with the moisture in the atmosphere to (32)_________ sulfuric acid and nitric acid. When it rains, these acids dissolve in the rain and turn it acidic. Acid rain is thought to be the worst pollution problem of all. It has (33)_________ aquatic life by turning many lake into lifeless bodies of water. In these areas, there is no limestone in the rocks to neutralize the acid rain naturally. One remedy is to pump limestone into the acidic lakes. (34)_________, it is not possible to do this on a large enough scale to save all the lakes.
Car exhaust fumes contain carbon monoxide and lead which are highly poisonous. In big cities, the exhaust fumes build (35)_________ and pose a health hazard to human beings.
Pollution of the sea by oil threatens marine life. Much of the oil comes from ships that clean their fuel tanks while at sea. Offshore oil wells also discharge vast amounts of oil into the sea. Pollution of the sea can also be caused by oil spills. An oil spill may occur as a result of accidents involving oil tankers.
A. on
B. in
C. up
D. over
Đáp án C
Build on: tin cậy vào
Build up: tích tụ lại
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Read the following passage and choose A, B, C, or D to indicate the correct word or phrase that best fits each of the following blanks. Fill in the appropriate word in question 33There are many sources of pollution in our modern world. At present, the most severe sources are acid rain, car exhaust fumes and oil spills.Factory chimneys give (31)_________ smoke that contains sulfur dioxide and nitrogen oxide. These gases combine with the moisture in the atmosphere to (32)_________ sulfuric acid an...
Đọc tiếp
Read the following passage and choose A, B, C, or D to indicate the correct word or phrase that best fits each of the following blanks. Fill in the appropriate word in question 33
There are many sources of pollution in our modern world. At present, the most severe sources are acid rain, car exhaust fumes and oil spills.
Factory chimneys give (31)_________ smoke that contains sulfur dioxide and nitrogen oxide. These gases combine with the moisture in the atmosphere to (32)_________ sulfuric acid and nitric acid. When it rains, these acids dissolve in the rain and turn it acidic. Acid rain is thought to be the worst pollution problem of all. It has (33)_________ aquatic life by turning many lake into lifeless bodies of water. In these areas, there is no limestone in the rocks to neutralize the acid rain naturally. One remedy is to pump limestone into the acidic lakes. (34)_________, it is not possible to do this on a large enough scale to save all the lakes.
Car exhaust fumes contain carbon monoxide and lead which are highly poisonous. In big cities, the exhaust fumes build (35)_________ and pose a health hazard to human beings.
Pollution of the sea by oil threatens marine life. Much of the oil comes from ships that clean their fuel tanks while at sea. Offshore oil wells also discharge vast amounts of oil into the sea. Pollution of the sea can also be caused by oil spills. An oil spill may occur as a result of accidents involving oil tankers.
A. destroyed
B. destroying
C. harming
D. harmed
Read the following passage and choose A, B, C, or D to indicate the correct word or phrase that best fits each of the following blanks. Fill in the appropriate word in question 32There are many sources of pollution in our modern world. At present, the most severe sources are acid rain, car exhaust fumes and oil spills.Factory chimneys give (31)_________ smoke that contains sulfur dioxide and nitrogen oxide. These gases combine with the moisture in the atmosphere to (32)_________ sulfuric acid an...
Đọc tiếp
Read the following passage and choose A, B, C, or D to indicate the correct word or phrase that best fits each of the following blanks. Fill in the appropriate word in question 32
There are many sources of pollution in our modern world. At present, the most severe sources are acid rain, car exhaust fumes and oil spills.
Factory chimneys give (31)_________ smoke that contains sulfur dioxide and nitrogen oxide. These gases combine with the moisture in the atmosphere to (32)_________ sulfuric acid and nitric acid. When it rains, these acids dissolve in the rain and turn it acidic. Acid rain is thought to be the worst pollution problem of all. It has (33)_________ aquatic life by turning many lake into lifeless bodies of water. In these areas, there is no limestone in the rocks to neutralize the acid rain naturally. One remedy is to pump limestone into the acidic lakes. (34)_________, it is not possible to do this on a large enough scale to save all the lakes.
Car exhaust fumes contain carbon monoxide and lead which are highly poisonous. In big cities, the exhaust fumes build (35)_________ and pose a health hazard to human beings.
Pollution of the sea by oil threatens marine life. Much of the oil comes from ships that clean their fuel tanks while at sea. Offshore oil wells also discharge vast amounts of oil into the sea. Pollution of the sea can also be caused by oil spills. An oil spill may occur as a result of accidents involving oil tankers.
A. forms
B. form
C. formed
D. forming