Câu 1: Tính pH của các dung dịch sau: a) dung dịch HCI 0,2 M b) dung dịch Ca(OH), 0,4M Câu 2 : Đốt cháy hoàn toàn 18,5 gam hợp chất hữu cơ (A) thu được 16,8 lít CO2 (đktc) và 13,5 gam H,O. Ti khối của A so với H, là 37. Xác định công thức phân tử và công thức đơn giản nhất của A. (Cho biết C= 12, H = 1; 0 =16, N= 14) Câu 3 :Hòa tan hết 6,95 gam hỗn hợp Al và Fe vào dung dịch HNO; đặc, nóng (dư) thu được 10,08 lít khí NO2 duy nhất (điều kiện tiêu chuẩn). Tính khối lượng mỗi kim loại trong hỗn hợp ban đầu giúp em với ạ em cảm ơn

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viết lại câu (có cấu trúc hoặc công thức đi kèm càng tốt) y/c lm đúng 86. There was never any answer when we rang. => Every…………………………………………………………………………………………… 87. That’s an insulting name to use for him. => Don’t call…………………………………………………………………………………….. 88. John asked if it was the blue one or the green she wanted. => Which………………………………………………………………………………………….. 89. She liked Paris very little, and Rome less. => She thought Rome…………………………………………………………………………. 90. I can meet you if you arrive before eleven. => So……………………………………………………………………………………………….. 91. They will catch all the prisoners again by tonight. => All the prisoners……………………………………………………………………………. 92. I’ve warned you not go to near that dog. => I’ve warned you about…………………………………………………………………… 93. No, please don’t tell him. => I’d rather………………………………………………………………………………………. 94. Why don’t ask her yourself? => I suggest……………………………………………………………………………………….

Bài 2. Bài tập hiện tại đơn, hiện tại tiếp diễn 1. Where's John? He _______________(listen) to a new CD in his room. 2. Don't forget to take your umbrella with you to London. You know it always ________ (rain) in England. 3. Jean ________(work) hard all day but she ________(not work) at the moment. 4. Look! That boy ________ (run) after the bus. He________(want) to catch it. 5. He ________(speak) German so well because he ________(come) from Germany. 6. Shh! The boss ________(come). We __________(meet) him in an hour and nothing is ready! 7. ________you usually ________(go) away for Christmas or________ you ________(stay) at home? 8. She ____________(hold) some roses. They__________(smell) lovely. 9. Oh no! Look! It ____________(snow) again. It always________________(snow) in this country. 10. Mary ___________ (swim) very well, but she ______________(not run) very fast. 11. ________ you ________(enjoy) this party? Yes, I __________(have) a great time! 12. Sorry I can't help you. I _____________(not know) where she keeps her files. 13. What ________you________(do) next Saturday? Nothing special. I ___________ (stay) at home. 14. I ___________ (think) your new hat ____________(look) nice on you. 15. I ________ (live) with my parents but right now I ________(stay) with some friends for a few days. 16. I can't talk on the phone now. I _____________ (drive) home. 17. Where are the children? They _____________ (lie) on the beach over there. 18. You never ________(listen) to a word I say! You ________always ________ (listen) to that mp3 player! 19. He ___________ (not understand) what you ____________ (talk) about. He's foreign. 20. How much ___________your suitcase ___________(weigh)? It ____________ (look) really heavy. viết đáp án là được ạ

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