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2 năm trước
Câu 1/ Phương trình nào sau đây là phương trình bậc nhất hai ẩn: A. xy + x = 3 B. 2x – y = 0 C. x + y = xy D. x 2 – y 2 = 0
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Giúp mình với T.T mai kiểm tra 1 tiết rồi BÀI 1: Viết phương trình hóa học (dưới dạng CTCT) của các phản ứng xảy ra khi cho : a, Metan tác dụng với Clo theo tỉ lệ mol 1:1 b, Propan tác dụng với Clo theo tỉ lệ mol 1:1 c, Tách 1 phân tử H2 từ Etan d, Etilen tác dụng với nước có xúc tác H+, nhiệt độ e, But-1-en tác dụng với HBr f, Trùng hợp CH2=CH2 g, Axetilen tác dụng với nước xúc tác HgSO4, H2SO4 h, Trùng hợp CH2=C (CH3) - CH=CH2 BÀI 2: Đốt cháy hoàn toàn m gam hỗn hợp X gồm 2 ankan là đồng đẳng kế tiếp, kết thúc phản ứng thu được 14,56 lít khí CO2 (đktc) và 16,2 gam nước a, Tìm 2 ankan trong hỗn hợp X b, Tính m BÀI 3: Hoàn thành sơ đồ chuyển hóa sau, ghi rõ điều kiện phản ứng nếu có (các PTHH viết ở dạng CTCT) a, C3H8 ------> CH4 ------> C2H2 ------> C2H4 ------> C2H5OH ------> C2H4 b, CaC2 ------> C2H2 ------> C2H3Cl ------> P.VC c, CH3COONa ------> CH4 ------> C2H2 ------> C2H6 ------> C2H5Br d, C2H2 ------> C4H4 ------> C4H6 ------> Caosubuna

A. LEXICO-GRAMMAR 1. Choose the best answer to complete the following sentences 1. A: “Those girls are very good at dancing!” - B: “ ___________” A. So do I! B. I know, they are C. Yes, they do! D. They were fine, thanks 2. I occasionally miss the bus so I have to take a taxi instead. A. never B. always C. sometimes D. rarely 3. There isn’t __________ for dinner, so I have to go to the market. A. any left B. some left C. any leaning D. some leaving 4. Public ___________ in this city is quite good, and it’s not expensive. A. journey B.travel C. vehicle D. transport 5. Bicycles ___________ in the driveway. A. must not leave B. must not be leaving C. must not be left D. must not have left 6. The film was so __________. However, my father saw it from beginning to end. A. interesting B. exciting C. boring D. fascinating 7. If the weather _____________ good, I _____________ camping with classmates. A. is / go B. is / will go C. will be / go D. will be / will go 8. Find the word which has a different sound in the part underlined. A. birthday B. mouthful C. breathe D. worth 9. Rob eats a lot of fast food and he __________ on a lot of weight. A. takes B. spends C. puts D. brings 10.You are not allowed to smoke in this hall. A. forbidden B. asked C. let D. made 11. “They listen to the music with great interest” means_____________ A. They enjoy the music. B. They hate the music. C. They dislike the music . D. They never listen to that music. 12. If people turn off all electric appliances in one hour all over the world, they can save lots of ______. A. electric B. electrical C. electrician D. electricity 13. These three Rs __________ reduce, reuse and recycle. A. stand up B. stand for C. ask for D. means 14. He _________ English in this school since he _____________ here. A. has taught/moved B. taught/moved C. taught/ has moved D. has taught/has moved 15. Find the word whose main stress pattern is different from others. A. beautiful B. interesting C. environment D. difference 2. Find a mistake in each sentence and correct it. 1. She asked us learned new words immediately before we left class. A B C D 2. What were you buy at the souvenir shop yesterday? A B C D 3. My brother plays video games twice times a week. A B C D 4. He comes here with bicycle because he does not like walking. A B C D 5. There are a little fruit trees in my grandparents’ garden. A B C D

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