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Câu 1: Hoàn thành các phương trình phản ứng sau:
Câu 2: Hãy xác định chất oxi hóa, chất khử, sự oxi hóa và sự khử trong phản ứng oxi hóa – khử sau:
H2 + HgO −to→ Hg + H2O
Câu 3: Có 3 lọ đựng riêng biệt các khí sau: oxi, không khí và hiđro. Bằng thí nghiệm nào có thể nhận ra các khí trong mỗi lọ?
Câu 4: Lập phương trình hóa học cho các phản ứng sau:
Cacbon đioxit + nước →axit cacbonic (H2CO3)
Lưu huỳnh đioxit + nước → axit sunfurơ (H2SO3)
Sắt + axit clohidric → sắt clorua + H2↑
Điphotpho pentaoxit + nước → axit photphoric (H3PO4)
Chì(II) oxit + hiđro→chì (Pb) + nước
Câu 5: Trong phòng thí nghiệm, người ta dùng hiđro để khử sắt(III) oxit và thu được 11,2 gam sắt.
Viết phản ứng hóa học xảy ra.
Tính khối lượng sắt(III) oxit đã phản ứng.
Tính thể tích khí hiđro đã tiêu thụ (đktc).
Đáp án và hướng dẫn giải
Câu 1:Hoàn thành các phương trình phản ứng:
Câu 2:
Câu 3: Đưa que đóm còn tàn đóm đỏ vào 3 bình khí trên. Bình khí làm que đóm bùng cháy là oxi.
Đốt 2 khí còn lại. Khi cháy với ngọn lửa màu xanh nhạt là H2, còn lại là không khí.
2H2 + O2 → 2H2O
Câu 4: Lập phương trình các phản ứng:
Cacbon đioxit + nước → axit cacbonic (H2CO3)
CO2 + H2O → HCO3
Lưu huỳnh đioxit + nước → axit sunfurơ (H2SO3)
SO2 + H2O →H2SO3
Sắt + axit clohiđric → sắt clorua + H2 ↑
Fe + 2HCl → FeCl2 + H2
Điphotpho pentaoxit + nước → axit photphoric (H3PO4)
P2O5 + 3H2O → H3PO4
Chì(II) oxit + hiđro → chì (Pb) + nước
PbO + H2 −to→ Pb + H2O
Câu 5:
PTHH:
Fe2O3 + 3H2 −to→ 2Fe + 3H2O (1)
(mol) 0,1 0,3 ← 0,2
Ta có: nFe = 11,2/56 = 0,2 (mol)
Từ (1) → nFe2O3= 0,1 (mol) → mFe2O3= 0,1 x 160 = 16 (gam)
Từ (1) → nH2= 0,3 (mol)
→ VH2= 0,3 x 22,4 = 6,72 (lít)
\(a.\left(2x-1\right)^2-\left(4x-3\right)\left(x+5\right)=0\) \(\Leftrightarrow4x^2-4x+1-\left(4x^2+17x-15\right)=0\)
\(\Leftrightarrow-21x+16=0\Leftrightarrow x=\dfrac{16}{21}\) . Vậy ...
b.\(x\left(x-1\right)=3\left(x-1\right)\Leftrightarrow\left(x-3\right)\left(x-1\right)=0\) \(\Leftrightarrow\left[{}\begin{matrix}x=3\\x=1\end{matrix}\right.\) . Vậy ...
c.\(\left(x-1\right)\left(3x-7\right)=\left(x-1\right)\left(x+3\right)\Leftrightarrow\left(x-1\right)\left(3x-7-x-3\right)=0\)
\(\Leftrightarrow2\left(x-1\right)\left(x-5\right)=0\Leftrightarrow\left[{}\begin{matrix}x=1\\x=5\end{matrix}\right.\) . Vậy ...
d.\(\left(x-3\right)^2+2x-6=0\Leftrightarrow\left(x-3\right)\left(x-3+2\right)=0\) \(\Leftrightarrow\left[{}\begin{matrix}x=3\\x=1\end{matrix}\right.\) . Vậy ...
cho mik hỏi bạn cần đề toán hình hay toán đại
Đề TA
I. Điền hình thức đúng của động từ trong ngoặc:
1/ The Sun (rise) in the east and (set) in the west.
2/ My grandma (use) to tell me the folktales.
3/ She (not ) playing soccer.
4/ Where you (be) going to visit next summer?
I (visit) Hue.
5/ They (work) in this company for ten years.
6/ My mother has to (clean)the floor everyday.
7/ He (not write)to his friend since Monday.
8/ Students must (go) to school on time.
9/ I (get) a letter from my old friend yesterday
10/ Where he (use to)live before he moved here?
II. Hoàn thành các câu sau, dùng hình thức so sánh phù hợp:
1/ My house isn't as (big) her house.
2/ Milk is (expensive) than mineral water.
3/ This hotel is (cheap) in the town.
4/ She is wearing a hat (same) mine
5/ Ho Chi Minh City is (big) than Ha Noi.
6/ February is (short) of the year.
7/Life in the city is (busy).
8/ Nam is (intelligent) in my class.
9/ Lan is (pretty) as her sister.
10/ Her hobbies are (different) from yours
IV. Điền vào mỗi chỗ trống với một giới từ đúng
1/ They have built this house..............a long time.
2/ We have lived .....An Lao.....14 years.
3/ There are some books........the table........the right corner.......the room
4/ The course begins......January and ends .....April.
5/ I usually watch TV ......the evening.
6/ The stadium is in............of my house.
7/ He often gets up..........5.30...........the morning but.......Sunday morning he gets up late.
8/ English learners learn words ..............different ways
9/ Thank you very much ...........lending me your bike
10/ I got good grades.............English and Math last semester
11/ All students enjoy taking part ............outdoor activities
12. Should should learn ............heart these new words.
V. Hoàn thành các câu sau dùng đại từ phản thân phù hợp
1/ My brother can repair the bike ....................
2/ They have a great time. They really enjoy ......................
3/ Don't worry about us. We can look after ...................
4/ This exercise isn't difficult. Do it ...................
5/ She cut ....................
6/ I made this shirt ....................
VI. Đặt câu hỏi cho từ gạch chân:
1/ Hoa went to school late this morning because her bike broke down
2/ I have to tidy the living room everyday
3/ She'll be home after dinner
4/ Lan used to live on the farm when she was young
5/ My mother gave me a new bike on my 14th birthday
6/ Nam often walks to school
7/ I need to improve Math and English
8/ Nga studied well this semester
9/ We have studied English for 4 years
10/ My best friend is very helpful and friendly
VII. Viết lại các câu sau sao cho nghĩa không đổi
1. "Can you carry these chairs into the house?"
Mrs Lan asked me ...........................................................................
2. "Please give me your book?"
He told me .......................................................................................
3. You shouldn't make noise in class."
The teacher said .............................................................................
4. "Can you help Tam with his English pronunciation?"
Mr Hung asked me ..........................................................................
5. My hobbies are playing sports and reading books
I love ................................................................................................
6. She was born on May 10th, 1996
Her birthday .....................................................................................
7. Nga must wash the dishes everyday
Nga has ...........................................................................................
8. We began to study English 4 years ago
We have ..........................................................................................
9. No one in class is as tall as Tam
Tam is the ........................................................................................
10. Women often did the house work without the help of modern equipment in the past In the past women used
VIII. Dùng từ gợi ý viết thành câu hoàn chỉnh
1. Thanh/ tall/ thin/ long/ straight/ hair
.........................................................................................................
2. His father/ generous/ friendly
.........................................................................................................
3. They/ going to/ have a meeting/ the weekend
.........................................................................................................
4. We/ must/not/ let/ children/ the kitchen/ because/ it/ dangerous place
.........................................................................................................
5. The Y&Y members/ going to/ take part/ recycling program/ save natural resources /and/ money/ the organization
.........................................................................................................
6. I/ a favor/ you help/ carry this bag?
.........................................................................................................
7. The town/ becoming/ beautiful
.........................................................................................................
8. My father/ used/ drive a car/ work/ now/ go/ bus
.........................................................................................................
9. I/ spend/ 2 hours/ day/ study English
.........................................................................................................
10. Alexander Graham Bell/ born/ Edinburgh/ March 3, 1847
.........................................................................................................
I. Điền hình thức đúng của động từ trong ngoặc:
1/ The Sun (rise) in the east and (set) in the west.
2/ My grandma (use) to tell me the folktales.
3/ She (not ) playing soccer.
4/ Where you (be) going to visit next summer?
I (visit) Hue.
5/ They (work) in this company for ten years.
6/ My mother has to (clean)the floor everyday.
7/ He (not write)to his friend since Monday.
8/ Students must (go) to school on time.
9/ I (get) a letter from my old friend yesterday
10/ Where he (use to)live before he moved here?
II. Hoàn thành các câu sau, dùng hình thức so sánh phù hợp:
1/ My house isn't as (big) her house.
2/ Milk is (expensive) than mineral water.
3/ This hotel is (cheap) in the town.
4/ She is wearing a hat (same) mine
5/ Ho Chi Minh City is (big) than Ha Noi.
6/ February is (short) of the year.
7/Life in the city is (busy).
8/ Nam is (intelligent) in my class.
9/ Lan is (pretty) as her sister.
10/ Her hobbies are (different) from yours
IV. Điền vào mỗi chỗ trống với một giới từ đúng
1/ They have built this house..............a long time.
2/ We have lived .....An Lao.....14 years.
3/ There are some books........the table........the right corner.......the room
4/ The course begins......January and ends .....April.
5/ I usually watch TV ......the evening.
6/ The stadium is in............of my house.
7/ He often gets up..........5.30...........the morning but.......Sunday morning he gets up late.
8/ English learners learn words ..............different ways
9/ Thank you very much ...........lending me your bike
10/ I got good grades.............English and Math last semester
11/ All students enjoy taking part ............outdoor activities
12. Should should learn ............heart these new words.
V. Hoàn thành các câu sau dùng đại từ phản thân phù hợp
1/ My brother can repair the bike ....................
2/ They have a great time. They really enjoy ......................
3/ Don't worry about us. We can look after ...................
4/ This exercise isn't difficult. Do it ...................
5/ She cut ....................
6/ I made this shirt ....................
VI. Đặt câu hỏi cho từ gạch chân:
1/ Hoa went to school late this morning because her bike broke down
2/ I have to tidy the living room everyday
3/ She'll be home after dinner
4/ Lan used to live on the farm when she was young
5/ My mother gave me a new bike on my 14th birthday
6/ Nam often walks to school
7/ I need to improve Math and English
8/ Nga studied well this semester
9/ We have studied English for 4 years
10/ My best friend is very helpful and friendly
VII. Viết lại các câu sau sao cho nghĩa không đổi
1. "Can you carry these chairs into the house?"
Mrs Lan asked me ...........................................................................
2. "Please give me your book?"
He told me .......................................................................................
3. You shouldn't make noise in class."
The teacher said .............................................................................
4. "Can you help Tam with his English pronunciation?"
Mr Hung asked me ..........................................................................
5. My hobbies are playing sports and reading books
I love ................................................................................................
6. She was born on May 10th, 1996
Her birthday .....................................................................................
7. Nga must wash the dishes everyday
Nga has ...........................................................................................
8. We began to study English 4 years ago
We have ..........................................................................................
9. No one in class is as tall as Tam
Tam is the ........................................................................................
10. Women often did the house work without the help of modern equipment in the past In the past women used
VIII. Dùng từ gợi ý viết thành câu hoàn chỉnh
1. Thanh/ tall/ thin/ long/ straight/ hair
.........................................................................................................
2. His father/ generous/ friendly
.........................................................................................................
3. They/ going to/ have a meeting/ the weekend
.........................................................................................................
4. We/ must/not/ let/ children/ the kitchen/ because/ it/ dangerous place
.........................................................................................................
5. The Y&Y members/ going to/ take part/ recycling program/ save natural resources /and/ money/ the organization
.........................................................................................................
6. I/ a favor/ you help/ carry this bag?
.........................................................................................................
7. The town/ becoming/ beautiful
.........................................................................................................
xin lỗi nhé ảnh thứ 2 mk gửi bị lỗi
ủa có gửi hở bn =)))