: Có 2 ống nghiệm đựng riêng biệt khí hiđro và khí oxi. Có 2 thuốc thử thường dùng sau đây: a. Que đóm đang cháy b. Bột CuO (màu đen) Dụng cụ coi như có đủ, hãy trình bày thí nghiệm để có thể nhận ra từng chất khí có trong mỗi lọ?

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EXERCISES FOR UNIT 9: FESTIVALS AROUND THE WORLD ( ENGLISH 7): I. Choose the word which has a different stress pattern from the others: 1. A. silent B. noisy C. pretty D. polite 2. A. degree B. student C. funny D. widen 3. A. agree B. hurry C. enter D. visit 4. A. fasten B. describe C. listen D. hover 5. A. culture B. turkey C. machine D. tourist 6. A. parade B. perform C. reverse D. copy II. Choose the best answer for each of the following sentences. 1. The ……………atmosphere is felt around all the villages. A. festive B. festival C. air D. tradition 2. A lot of cultural and ………….activities are held as part of the Flower Festival in Da Lat. A. arts B. artist C. artistic D. art 3. It is…………….to see elephants racing in the Elephant Race Festival in Dak Lak. A. amaze B. amazing C. amazed D. amazement 4. A lot of dancers go to Rio de Janeiro to…………the Rio Carnival. A. play B. take C. attend D. follow 5. Everybody has gone to the…………..festival. A. music B. musical C. musicians D. musician 6. The…………..of the Rio Carnival is the Samba Parade. A. importance B. best C. highlight D. performance 7. People in Cannes take the Cannes Film Festival………….a very serious way. A. in B. at C. on D. with 8. The festival………….every year at the end of August. A. takes B. takes place C. occur D. held III. Make questions for the underlined parts: 1. The Festival of the Sun is held on June 24th. ............................................................................... 2. My mom saved money to travel to America. ............................................................................... 3. They decorate their house with beautiful Christmas trees. ...............................................................................