Ai giúp em làm 3 câu trách nhiệm hóa với ạ Câu 8: Nguyên tố A có số hiệu nguyên tử là 11, chu kì 3 nhóm I trong bảng tuần hoàn các nguyên tố hóa học. Nguyên tố A có kí hiệu hóa học là A. Na. B. Ca. C. Ba. D. K. Câu 9: Hoà tan vừa hết 10 gam hỗn hợp 2 oxit CuO và Fe2O3 trong 50 ml dung dịch HCl 7M. Khối lượng của CuO trong hỗn hợp ban đầu là A. 2 (gam). B. 4 (gam). C. 6 (gam). D. 3 (gam). Câu 10: Hòa tan hoàn toàn 112 gam canxioxit vào nước dư. Khối lượng sản phẩm thu được sau khi phản ứng kết thúc là A. 74 (gam). B. 7,4 (gam). C. 148 (gam). D. 14,8 (gam

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REVISION I. Complete the sentences using the past simple form of the verbs. ( CHIA ĐỘNG TỪ TRONG NGOẶC DÙNG THÌ QUÁ KHỨ ĐƠN ) 1- I (be).......................................a student 2 years ago. 2- He (be).................................. a doctor two years ago. 3- They (be)................................. farmers last year. 4- Lan and Ba (be) .........................nurses last year. 5- It (be not)............................ cold yesterday. 6- She (be not)........................a pupil last week. 7- This hat (be not) .........................new yesterday. 8- My parents (be not) .......................teachers two years ago. 9- He (be not) ..........................a mechanic last Monday. 10- (Be)................... he an engineer yesterday. No , he (be not)..................... II.Complete the sentences using the past simple form of the verbs. 1. I _____ at home all weekend. ( stay) 2. Angela ______ to the cinema last night. (go) 3. My friends ______ a great time in Nha Trang last year. (have) 4. My vacation in Hue ______ wonderful. (be) 5. Last summer I _____ Ngoc Son Temple in Ha Noi. (visit) 6. My parents ____ very tired after the trip. ( be) 7. I _______ a lot of gifts for my little sister. (buy) 8. Lan and Mai ______ sharks, dolphins and turtles at Tri Nguyen aquarium.(see) 9. Trung _____ chicken and rice for dinner. (eat) 10. They ____ about their holiday in Hoi An. (talk) 11. Phuong _____ to Hanoi yesterday. (return) 12. We _____ the food was delicious.(think) 13. Yesterday, I (go)______ to the restaurant with a client. 14. We (drive) ______ around the parking lot for 20 mins to find a parking space. 15. When we (arrive) ______ at the restaurant, the place (be) ______ full. 16. The waitress (ask) ______ us if we (have) reservations. 17. I (say), "No, my secretary forgets to make them." 18. The waitress (tell)______ us to come back in two hours. 19. My client and I slowly (walk) ______ back to the car. 20. Then we (see) ______ a small grocery store.