Đốt cháy hoàn toàn m (g) hợp chất hữu cơ A cần dùng 11,2g khí oxi, thu được 8,8g CO2 và 5,4g H2O. Ở đktc 2,24l khí A có khối lượng 3g. Xác định CTPT của A ?

Giúp nha bài này hơi khó nhưng mà điểm cao 50 điểm ko dài đâu có 6 câu thoi

Mọi người giải hộ em đề toán này vs ạ.

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Câu 31. By cutting down trees we ..........the natural habitat of birds and animals. A. damage B. harm C. hurt D. injure Câu 32. The newspaper report contained........important information. A. many B. a lot of C. an D. another Câu 33. Trees and shrubs ........ an important part in preserving land because their roots bind the soil and retain water. A. make B. keep C. have D. play Câu 34. You can't leave the country....... a passport. A. no B. without C. if not D. unless Câu 35. We are facing the possible.........of most of our rain forests. A. vanishing B. disappearance C. extinction D. ruin Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s): Câu 36. They had to think of some other ways of bettering their lives A. improving B. killing C. worsening D. cutting Câu 37. The farmer removed some undeveloped trees to improve the growth of the rest. A. planted B. watered C. eliminated D. fertilized Câu 38. Deforestation is destroying large areas of tropical rain forest. A. changing B. raising C. becoming D. damaging Câu 39. We visited the Nairobi National Park and enjoyed different species of fauna. A. zoo B. animal C. flowers D. plant Câu 40. Contamination is threatening the park and many species of animals living in it. A. elimination B. population C. distribution D. pollution

thể tích ở điều kiện tiaau chuẩn của 2 mol khí O2 là

Giải giúp mình, 20 câu lịch sử 11 hứa 5 sao

Câu 22. I didn’t get a taxi because I didn’t have any money on me. a. If I had some money on me, I would get a taxi. b. If I have some money, I will get a taxi. c. If I had had some money, I would have got a taxi. d. If I did have money, I did get a taxi. Câu 23. The life ......... of sperm whale can be up to seventy years. A. distance B. period C. length D. span Câu 24. Without plants, most of water would ……………………….as soon as it falls. A. run off B. run after C. run away D. run by Câu 25. I still can’t believe it! My bicycle................ last night. A. was stealing B. stolen C. was stolen D. stole Câu 26. It rained all the time, ................was a great pity. A. that B. what C. which D. who Câu 27. Yesterday afternoon, I went to the post office _______ some letters. A. sends B. sent C. send D. to send Câu 28. Tents come in _______ shapes and sizes A. vary B. variety C. various D. variously Câu 29. The room is being ____________ at the moment A. was cleaned B. cleaned C. cleaning D. clean Câu 30. This room isn’t very interesting. They _____________ put some pictures on the walls. A. will B. should C. shouldn’t D. won’t

M ọingười giải hộ em phần đọc hiểu vs ạ

Câu 11. “How about meeting at the school gate at 8:30?” – “Yes, ……………..” a. that’s a great idea b. I don’t think it a good idea c. I’m busy at that time d. I’m sorry I can’t Câu 12. I will catch the usual train ………….Friday evening. a. in b. at c. on d. of Câu 13. It’s lovely …………….that you are going to spend the next weekend in the countryside. a. hear b. hearing c. heard d. to hear Câu 14. Thanks ………….your invitation. a. about b. for c. of d. with Câu 15. Cuc Phuong is …………….160 meters South West of Hanoi. a. locate b. located c. location d. locating Câu 16. If I ………….you were ill last week, I would have gone to see you. a. know b. knew c. had known d. knows Câu 17. If you had called him, he ………………. a. would come b. will come c. wouldn’t come d. would have come Câu 18. Tom got to the station in time to catch the train. If he …………….it, he …………….late for his interview. a. missed / would be b. misses / will be c. missed / would have been d. had missed / would have been Câu 19. If you ……………to lock the door, it wouldn’t have been stolen. a. remember b. remembered c. had remembered d. would remember Câu 20. If I ………….you, I would plant more trees around the house. a. am b. was b. had been d. were Câu 21. We ……………..at the party if you hadn’t spent so long in the café.