Đáp án:
1. 4Fe + 3O2 → 2Fe2O3
Hiện tượng: xuất hiện kết tủa màu nâu đen
2. Phản ứng hóa học là quá trình biến đổi từ chất này thành chất khác.
VD: Cacbon + Oxi → Khí cacbonic
C+O2->CO2
Giải thích các bước giải:
Use the word given in the bracket to form a word that fits in the space. 1. We must be ………………………..…. when we cross the road. CARE 2. I usually go to the ………………………to buy bread. BAKE 3. I’m Vietnamese. What’s your……………………….? NATION 4. He is the …………………… soccer player in the team. BAD 5. Our roads are ……………………..places. DANGER 6. There are four. ………….………….in my house. BOOKSHELF 7 . It is ………………… to eat a lot of sweetened food and drinks. HEALTH 8. My neighborhood is ……………..…….for good and cheap restaurants. FAME 9. My sister and my mother are good ……………….……... COOK 10. I was born on the …………………. of March, 2003 TWENTY
Hãy nêu ưu điểm và khuyết điểm của mạch điện một công tắc ba cực điều khiển hai đèn
There is a mistake in each sentence. Find and correct it. 1. We are usually tired in the summer so it’s hot. 2. He doesn’t never goes fishing in the winter. 3. Mary is traveling by bus and visit a lot of interesting places. 4. What do factory do with waste and scrap? 5. English is one of my favorite subject. 6. One of my brothers have two eggs and some bread for breakfast. 7. Our teacher gives us much homeworks today. 8. My sister often goes to school with an orange small bag. 9. Mai always helps her mother in the housework. 10. Would you like an apple or any orange juice?
x/9=y/6=-24/36 Kiếm vở hoài chả ra bài này chỉ em với
Choose the best answer from the four options (A or B, C, D) to complete each of the following sentences. 1. __________a strange man outside the house. A. He’s B. It’s C. There’s D. This is 2. __________likes John. He’s very popular. A. Every one B. All people C. Nobody D. Anyone 3. Can you __________me the time, please? A. say B. tell C. speak D. lend 4. __________care when you bring that dish. It’s hot. A. Be B. Have C. Make D. Take 5. Kyoko wants to make __________with the other students in the class. A. friend B. friends C. friendly D. friendship 6. Listen! The news on the radio __________very interesting. A. are B. is C. has D. have 7. There are __________eggs in the supermarket. A. hundreds of B. hundreds C. hundred of D. of hundreds 8. He lives __________the corner of Green Street and Links Road. A. with B. by C. at D. on 9. Why don’t we go to the zoo? ~ __________. A. Because I’m going B. Let’s drive there C. It takes an hour D. That’s a good idea 10. Mary is the __________of the two girls. A. small B. smallest C. smaller D. smaller than 11. How far is it from your house to school? ~ __________. A. About ten miles B. About two hours C. At 10 o’clock D. In some minutes 12. “ Thanks for inviting me to your birthday party ? “ - “ ……………….” A. OK B. Don’t worry C. You’re welcome D. Great 13. Mr. Long has ............................... days off than Mr. Tuan. A. many B. less C. fewer D. much 14. I had to stand in the balcony to catch the whole …………….. of the parade. A. view B. picture C. sight D. vision 15. Give a ………………. before you turn left or right. A. sign B. turn C. sound D. signal
Giúp em mình nha mình sẽ cho quà và thưởng
Choose the word which has the underlined part pronounced differently from the others. 1. A. forest B. emty C. environment D. fastest 2. A. says B. plays C. days D. stays 3. A. planet B. trash C. understand D. waste 4. A. marathon B. therefore C. weatherman D. together 5. A. pronounce B. announce C. mouth D. enough 6. A. heavy B. peaceful C. weather D. restaurant 7. A. think B. visit C. children D. decide 8. A. grow B. how C. know D. low 9. A. nature B. mountain C. waterfall D. festival 10. A. fridge B. quiet C. firework D. island
Ta chủ động phân tản lực lượng địch ra sao Bài 27 í ạ.... Em cần mn giúp dùm em
Read the text carefully and then choose the best option A, B, C or D: (1)…….the United States, many adults and children…..(2)…..overweight. Some people eat……..(3)……food at meals. They also eat snacks between meals. Sometimes people eat healthy snacks like fruit or vegetables….(4)….many Americans eat a lot of junk food such as cookies, candy and potato chips. Eating junk food can….(5)…….people gain weight. People also gain weight…….(6)…...they don’t get enough………..(7)………People need to walk, run , ride bicycles, or walk out in health clubs and gyms. When people exercise, they……..(8)…. good and have more energy. A good diet and exercise will help you……..(9)….along and………(10)…….life. 1. A. on B. In C. At D. from 2. A. is B. was C. were D. are 3. A. too many B. too much C. few D. plenty 4. A. but B. because C. although D. so that 5. A. get B. lead C. urge D. make 6. A. so B. however C. but D. because 7. A. exercises B. work C. money D. energy 8. A. become B. taste C. have D. feel 9. A. live B. lives C. living D. to living 10. A. health B. safe C. fair D. healthy
Complete this conversation between two friends using sentences marked by A-H. There are 2 extra sentences which you do not need to use. Jenny: It’s my birthday party on Friday. Can you come? Paula: (1)…………………………………. Jenny: That’s right- at eight o’clock. But I’ve got a lot to do before that Paula: (2)…………………………………. Jenny: Well you could come with me tomorrow to buy some food Paula: (3)…………………………………. Jenny: That’s good idea. Shall we leave at about nine? Paula: (4)…………………………………. Jenny: Ten then. I’ll come to your house and we’ll leave when you’re ready. Paula: (5)…………………………………. Jenny: Let’s just buy pizza and cakes. Something quick and easy. Paula: (6)…………………………………. Jenny: See you tomorrow then. A. I have to study first. How about a bit later? B. Good idea! Everyone likes those. C. I’d love to. Is it in the evening? D. If you like. Do you want to go in my car? E. Yes. I’ll be there at ten. F. What do we need to get? G. I’m afraid I’m at work that day H. Would you like me to help?
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