cho 250ml dung dịch naoh 4M vào 50ml al2(so4)3 2M. Sau phản ứng thu được dung dịch X. Thành phần các chất trong X gồm A. Na2SO4 và Al2(so4)3 B. na2so4 và naoh C. na2so4 và al(oh)3 D. na2so4, NaAlO2, naoh

Hòa tan hoàn toàn 11,2g Fe vào HNO3 dư, thu được dung dịch A và 8,96 lít hỗn hợp khí X gồm NO và một khí X với tỉ lệ thể tích 1 : 3. Các thể tích đo ở cùng điều kiện. Khí X là
A. N2O.     B. NH3.    C. N2.     D. NO2

Khi cho m gam Fe tác dụng vừa đủ với V lít dung dịch HNO3 thu được dung dịch
muối, 0,1 mol khí NO và 0,3 mol khí NO2. Xác định m.
A. 12,5g B. 11,5g C. 11,2g D. 15,2g.

Hòa tan 4,5 gam Al bằng dung dịch HNO3 loãng được V lít khí NO và V1 lít khí N2O. Hỗn hợp khí có tỉ khối so với H2 = 16,75. V và V1 gần với giá trị nào sau đây? 

A. 2,24; 1,12                 B. 1,98; 0,66 

C. 1,12; 1,12                 D. 2,24; 0,88

Rewrite the sentences:

1. They didn’t leave the house early so they were late for the play.

-> If they ……………………………………………………

2. Unless it stops raining, we won’t go out.

-> If it ………………………………………………….

3. You caught cold because you didn’t keep your feet dry.

-> If you ……………………………………………………………..

4. Review the lesson carefully; otherwise you can’t do the test well.

->  Unless you……………………………………………………

5. “If you happen to see the man, you may give this book to him.” He said to the girl.

-> He said to the girl ……………………………………………………

6.  “I wouldn’t have been upset if she had written to me earlier,” the man said.

-> The man said ……………………………………………………

7.  “The boss would complain if we didn’t report it to him.” David said to his colleagues.

-> David said ……………………………………………………

8.  “Mum would be cross if you went on doing like this,” the girl said to her younger brother.

-> The girl said ……………………………………………………

WRITING: Complete the second sentence so that it has a similar meaning to the first one, using the words given:

1. He stayed at home last week because he was ill.

-> If..............................................................................................................

2. Nam said to his mother, “If I get a scholarship, I will study abroad.”

-> Nam told his mother …………………………………..

3. “What would you do if you were the Prime Minister, John?” I said

-> I asked …………………………………….

4. Don’t leave the lights on all night, you will waste electricity.

-> If ………………………………………………

5. Do as I tell you that or you’ll regret about it.

-> Unless …………………………..

6. Peter was a careless driver. If he doesn’t take more care, he’ll have an accident.

-> Unless ………………………….

7. But for his help, I’d have gone bankrupt.

-> If …………………………

8. He’s very thin, that’s why he feels the cold so much.

-> If he.......................................................................................................

9. Without his help, we would have died.

-> If it ……………………….

10. “If you had told me yesterday, I would have helped you,” said the man.

-> The man said…………………………

WRITING: Complete the second sentence so that it has a similar meaning to the first one, using the words given:

1. “Tom, you can’t smoke cigarettes here,” the boss said to Tom.

-> The boss prevented ……………..

2. “You copied your friend’s paper, Jack”, the teacher said.

-> The teacher accused ……………………..

3. “It’s very kind of you to help me use this computer software. Thank you.” John said to Paul.

-> John thanked ………………..

4. The boy said that he had lost his bicycle.

-> The boy admitted …………………

5. I’ve warned you not to go near that dog.

-> I’ve warned you against ……………………

6. “If I were you, I’d look for another job.”

-> I suggested ……………………….

7. She had to do the washing up but she didn’t.

-> She forgot ……………………

8. “Tan, I gave you 50,000 dong yesterday,” Pat said to Tan.

-> Pat insisted ……………………………..

9. Mrs. Taylor regretted buying a second-hand washing machine.

-> Mrs. Taylor wishes ………………………………….

10. “I have always wanted to be a pilot”, Paul said to you.

-> Paul has always dreamt......................................................