Bài 8: Hòa tan 1,12 gam sắt vào 100 ml dung dịch axit sunfuric nồng độ 1M. a. Nếu nhúng giấu quì tím vào dd sau phản ứng thí quì tím có đổi màu không ? Giải thích. b. Tính thể tích khí thu được ở đktc . c. Tính khối lượng muối thu được sau phản ứng. d. Tính nồng độ mol của dung dịch muối thu được sau phản ứng. Biết thể tích dung dịch thay đổi không đáng kể.

I. Change the active into the passive 1. Does Jackson give that lecture? - ………………………………………………………………………. 2. The children often read stories in the evening. - ……………………………………………………… 3. People speak Spanish in many countries. -……………………………………………………………. 4. They grow rice in the north. -………………………………………………………………………….. 5. We don't raise cows on our farm. -……………………………………………………………………... 6. Japan makes a lot of cars. -…………………………………………………………………………….. 7. I didn't write that letter. -………………………………………………………………………………. 8. Shakespeare wrote that play. -…………………………………………………………………………. 9. Alice didn't make that cake. -…………………………………………………………………………. 10. A man asked me several difficult questions at the interview. - 11. The club bought him 2 years ago for a fee of $20 000. - ………………….. 12.She is using the computer at the moment. -…….. 13. They are opening a new ring road round the city. -……… 14. They are building some new houses down the street. -……. 15. Alex is preparing that report. -….. 16. Is Mrs. Brown painting your house? -…. 17. They are building a market near the hospital. -…. 18. When we came, they were repairing the roof of the house. -….. 19. Tom was writing two poems. 20. She was wearing her new T-shirt when I met her yesterday. 21. Ann was writing a letter. 22. The chief engineer was instructing all the workers of the plan. 23.They have moved nothing in your room. - 24. Has Tom finished the work? 25. She has not changed the flowers. -….. 26. They have prepared tables for lunch. -….. 27. Someone had stolen his car. -…. 28. Someone had broken the windows. -…. 29. Have they changed the window of the laboratory? 30. Bill will invite Ann to the party. -…..

Bài 7: Cho kim loại kẽm tác dụng vừa đủ với 147 gam dung dịch axit sunfuric nồng độ 10%. a. Tính thể tích khí thu được ở đktc b. Tính nồng độ % của dung dịch muối thu được sau phản ứng.

Mọi Người cho mình hỏi ví dụ khi một bài toán kêu tính góc B thì ta tính sin b hả

8. She speaks three languages. ________________________________________? 9. She lives in the country. ________________________________________?

CM: l N l > N biết N= M-16 M=(x - 2) ³ - (x - 2) (x ² + 2x +4)

cmr: (3^2012)-9 chia hết cho 13

Phân tích đa thức thành nhân tử a) $a^{6}$ + $a^{4}$ + $a^{2}$ $b^{2}$ + $b^{4}$ - $b^{6}$ b) $x^{3}$ + 3xy + $y^{3}$ - 1

11. There is a special_______for Japanese girls on March 3rd every year. A. celebrate B. celebration C. celebratory D. celebrating 12. _________do people celebrate the festival? - They celebrate it in a special way. A. How often B. What C. Why D. How 13. Non-renewable energy sources like coal, natural gas and_________produce a lot of carbon dioxide. A. wind B. hydro C. oil D. solar

Giúp mik `3` ý này Cảm ơn nhiều ạ!