Cân bằng các phương trình hóa học sau: 1) Fe + O2 -------------- > Fe3O4 2) Al + O2 Al2O3 3) P + O2 P2O5 4) SO3 + H2O H2 SO4 5) P2O5 + H2O H3 PO4 6) KMnO4 K2MnO4 + MnO2 + O2 7) H2 SO4 + KOH K2 SO4 + H2O 8) SO2 + O2 SO3 9) H3 PO4 + NaOH Na3PO4 + H2O 10) CO2 + Ca(OH)2 CaCO3 + H2O

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Choose the correct answer to complete each of the following sentences. Write your answers in the space provided. (7.0 points) 1. I bought this dress at the ________on Hung Vuong street. A. clothes’store B. store of closes C. clothes store D. closing store 2. Isn’t it easy to learn English well? A. No, it is B. No, it does not C. Yes, it is D. Yes. it does 3. There are two churches in the town and________ of them are extremely old. A. each B. all C. both D. most 4. Our neighbors are very ________ on camping holidays. A. interested B. fond C. eager D. keen 5. Mr. Nam ________to work yesterday. A. wasn’t drive B. not drive C. didn’t drove D. didn’t drive 6. The news on TV last night________ very good. A. was B. has C. were D. be 7. Lan did not know this word. Hoa didn’t, ________ . A. so B. neither C. either D. too 8. My sister will be 16 ________ Sunday ________. A. on - May 25th B. on - May 25 C. in - 25th May D. in - May 25 9. If he eats all that food, he eats ________ A. quite much B. too many C. quite many D. too much 10. Mr. Robinson speaks Vietnamese very________. A. skillfully B. good C. fluently D. best 11. Sunflowers grow ________ in areas where there is much sunlight. A. beautifully B. beautifying C. beauty D. beautiful 12. ________the man gets, ________he becomes. A. The more old/ the more weak C. The older/ the weakest B. The older/ the weaker D. Older/ weaker 13. She gave an interesting book ________ me. A. to B. for C. of D. at 14. The doctor advised Tom to stop ________. A. for smoking B. smoke C. smoking D. to smoke 15. Yesterday, I had a bad day. I got up very late and ________my bicycle was broken. A. lucky B. unlucky C. luckily D. unluckily 16. This river is very ________ for the swimmers. A. danger B. dangerous C. dangerously D. more dangerous 17. We prefer reading ________ playing chess. A. with B. than C. as D. to 18.What would you like ________ to? Pop music. A. to listen B. listen C. listening D. listen 19. The test we did last time was more difficult than this one. A. We did a difficult test last time and a more difficult one this time. B. This test is not as difficult as the one we did last time. C. We had a more difficult time last week than this one. D. The test we have this time is not difficult at all. 20. Jogging is very useful. A. I find it is useless to jog. C. It is very useful to jog. B. Jogging is not good. D. We should not jog. 21. How is Hoa’s new school different________her old school? A. from B. to C. with D. about 22. Tim’s father has________summer vacation. A. three-weeks B. three-week C. a three-week D. a three-weeks 23. I’d like some local stamps and some for__________. A. overseas B. over sea C. over seaing D. an oversea 24. How much is it________a local letter in Malaysia. A. mail B. to mail C. mailing D. mails 25. Last night, the dentist__________a cavity in Peter’s tooth. A. made B. brushed C. filled D. put 26. My parents want me ________ hard every day. A. study B. to study C. studying D. to studying 27. She added________salt to the dish so it tasted good. A. a little B. many C. a few D. a lot 28. My mother wants a________ apples. A. lot B. lots of C. little D. dozen 29. Don’t spend too much of your time________video games in the arcade. A. play B. to play C. plays D. playing 30. Please________the milk carefully. I don’t want it to boil over. A. see B. watch C. look at D. notice 31. Susan is from Great Britain so she speaks________. A. British B. English C. French D. England 32. Minh likes sports very much. He usually plays ________ after school . A. games and geography B. soccer and literature C. volleyball and soccer D. volleyball and swimming 33. She looked at my teeth and told me ________. A. not worry B. not worrying C. not to worry D. to not worry 34. Children must take ________activities with others. A. after B. off C. into D. part in 35. Computers are very ________in the designing industry. A. important B. importance C. importances D. unimportant