1) Phân biệt, nhận biết, tách và tinh chế các chất a) dung dịch HCl, KCl, KBr, NaI b) dung dịch I2, Na2CO3, NaCl, NaBr c)dung dịch KOH, HCl, HNO3, K2SO4,BaCl2 d) chất rắn CaCO3, K2CO3, NaCl, KNO3 e)chất rắn AgCl, KCl, BaCO3, KI

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IV. Fill in the blanks Dear Lan, I’m ……………………..(0) to invite you to a party we ………………….(1) at the flat next Friday , December 14th . As you know, …………………….Lien’s 13th birthday next week and my birthday next month, ……………………..(3) we thought we’d celebrate together and have a joint party. I can’t remember if you know my address or not, but anyway, if you ………………… (4) the directions below, you shouldn’t get lost. Take the Number 15 bus from the station and ……………….(5) at the Star Hotel. Walk down Long Viet Road, past the Dan Chu Cinema, and then …………………… (6) the first turning on the right. That’s Le Loi Road. Turn left ………………..(7) the first junction, then go straight past the church as far as the next crossroads . …………………(8) and our block of flats is the second on the right. Do try and come. Of course you’re ………………….(9) to bring someone with you if you want to. Look forward ………………….(10) you then! Love, Mai 0. A. writing B. write C. writes D. to write 1 A. have B. are having C. going to have D. will has 2 A. it’s B. its C. they’re D. she’s 3 A. too B. but C. because D. so 4 A. to follow B. follow C. following D. follows 5 A. get up B. get by C. get on D. get off 6 A. have B. get C. take D. bring 7 A. in B. at C. of D. on 8 A. Right turn B. To right C. To turn D. Turn right 9 A. welcomed B. welcome C. welcoming D. to welcome 10 A. to see B. for seeing C. of seeing D. to seeing V.Write the correct form of the verb in brackets 1.. Jonh (watch)____________TV when his friend (ring)____________him up last night. 2. You (be)______________________able to speak English better if you (learn)______________________harder. 3.How much time do you spend (watch)______________________TV every day ? 4. Nam (not visit)___________the museum with his class last Sunday because he (catch)___________a cold. 5. Boys like (play)___________marbles or catch while girls enjoy (skip) ___________rope or chatting. 6.Keep silent. please.Our teacher (explain)_______________________the lesson. VI.Fill in the blank with one suitable preposition 1.In a game of singles, two players play_________ each other. 2.I’m not very fond _________ detective stories. 3.Margarine is different _________ butter. 4.His parents are very strict_________ him. 5.Many people take pan_________ riding a bike. 6.We’d like a walk instead _________ jogging every morning. 7.Huy is very good_________ fixing tilings. 8.They study and listen to music _________ the same time. 9. _________ literature, we learn about books and write essays. 10.Will you be home_________ dinner tonight ?