Cho các chất : KMnO4, CO2, H2O, SO3, HgO, NaNO3, KClO3, Na,Ca, P2O5, BaO, Mn2O7. Hỏi những chất trên, có những chất nào : a, Nhiệt phân ra O2? b, Tác dụng với nước ở nhiệt độ thường, tác dụng với nước vôi trong, tác dụng với khí oxi ở nhiệt độ thích hợp ?

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II. Vocabulary: Choose A, B, C or D to complete the following sentences 1.We decided not to go out for meal ___________ we were too tired. a. but b. because c. so d. and 2. Mary’s eyes are weak, ___________ she has to wear glasses. a. but b. however c. and d. so 3. ___________ put all the guests on the floor? a. Why don’t we b. I suggest c. how about d. Let’s 4. My school is …………………than Lan’s school. a. big b. biggest c. bigger d. small 5. A new air conditioner will be _________ this morning. a. to install b. installed c. installing d. install 6. We can _________ easily in the daylight. a. to read b. reading c. readed d. read 7. She ………………….be 14 on her next birthday. a. will b. is c. does d. can 8. Phanxipang is the …………………..mountain in Vietnam. a. high b.higher c. height d. highest 9. Is he an actor __________ a singer? An actor a. and b. or c. with d. so 10. He was tired, ___________ he took a rest before continuing the work. a. so b. and c. but d. if III . Change these sentences into passive voice 1. My grandfather planted this tree. ...................................................................................................................... 2. Nobody has collected the rubbish. ..................................................................................................................... 3. Will they build a new school very soon? ...................................................................................................................... 4. Hung gave me a beautiful glass on my birthday. ...................................................................................................................... 5. We do a lot of work every day. ...................................................................................................................... 6. They cut down many trees to make paper. ...................................................................................................................... 7. People consider English the most international language. ...................................................................................................................... 8. You should shut these doors before 5 pm. ...................................................................................................................... 9. Pollution from factories has destroyed many lakes and rivers. ...................................................................................................................... 10. They don't use the room very often. ...................................................................................................................... IV . Rewrite the sentences 1.Hoa and Tim are both 13 years old.( the same age ) -> Tim is_____________________________________________. 2.She speaks English well, and her sister speaks well too.(as……as) -> She speaks________________________________________ her sister. 3.I’m quite tall but you are taller.(as……as) ->I’m__________________________________________________ 4.I thought she was intelligent; but she is so stupid.(different from) ->She is_________________ what_____________________________ 5. We started learning English three years ago We have_______________________________________________ V. Put the verbs in brackets into the correct tense. 1. I (not do) _______________ morning exercises when I (be) _______________ young. However, I (do) _______________ exercises every morning now. 2. I often (get) _______________ up at 6.00 in the morning. 3. This morning, I (get) ___________ up very late, because I (stay) ___________ up late last night. 4. I (watch) _______________ a movie on TV now. It (be) _______________ on TV yesterday but I (not have) _______________ free time to see. 5. What time __________________you (have) _______________ breakfast every day? 6. Minh (brush) _______________ his teeth after meals so his teeth (be) _______________ very good. 7. Don’t (be) _____________ foolish! 8. You shouldn’t (sleep) _______________ too much. 9. I (get) _______________ a letter from my old friend yesterday 10. He (not write) _______________ to his friend since Monday.