Hòa tan hoàn toàn 6,9 gam natri vào nước tạo thành m gam natri hydroxit(nạp) và thấy có 2,24l khí hydro thoát ra(đktc). Hãy cho biết: a) Khối lượng natri đã phản ứng b) Giá trị m

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Choose the word whose underlined part is pronounced differently from that of the others. 1. A. fun B. run C. music D. sun 2. A. question B. education C. collection D. vacation 3. A. please B. teacher C. reader D. break Choose the best answer to each of the following sentences. 4. What a great _________! They always play very well. A. band B. bank C. bench D. vessel 5. You _________finish this question for math tomorrow. A. have to B. has to C. had to D. having 6. He spends most of his free time _________ video games. A. to play B. play C. playing D. plays 7. Bao usually plays soccer _________. He is a _________ player. A. well/well B. well/good C. well/bad D. good/badly 8. –A: _________did you see her? –B: I saw her yesterday morning. A. When B. Where C. What time D. How 9. I don't like coffee. Mai doesn't like it, _________. A. neither B. either C. too D. so 10. Ha likes candy. _________do we. A. Neither B. Too C. Either D. So 11. –A: Let's _________to the zoo after class. –B: It’s a good idea! Let’s do that! A. go B. goes C. going D. to go 12. Last week, Mai’s mother _________a sick note for her. A. write B. wrote C. to write D. writing 13. Nam _________his teeth after meals and before going to bed every day. A. to brush B. brush C. brushing D. brushes 14. Stop, please! That’s too _________sugar. A. many B. some C. much D. few 15. Math, History, English are _________ at schools. A. periods B. subjects C. languages D. exams 16. –A: How _________do you play those games? –B: Once or twice a week. A. usual B. much C. often D. long 17. I feel much _________today than I did yesterday. A. well B. good C. better D. best 18. –A: What _________is your car? –B: It’s black. A. color B. colors C. colorful D. colorless 19. The family rented _________apartment next door to mine. A. a B. an C. some D. any 20. Your _________is 37°C. It's normal. A. height B. temperature C. weight D. meter 21. –A: _________have dinner with us tonight? –B: Yes, I'd love to. A. Do you like to B. What about C. Would you like to D. Let's 22. You ought to _________to the dentist regularly. A. going B. went C. go D. will go Circle the odd one out. 23. A. shark B. dolphin C. turtle D. cavity 24. A. balanced B. unhealthy C. sensibly D. moderate 25. A. spinach B. papaya C. durian D. pineapple 26. A. cough B. temperature C. sneeze D. blow