một hợp chất gồm 2 nguyên tố Fe và O biết mFe/mO=7/3 biết PTK của hợp chất là 160 đvc Tìm số nguyên tử của Fe và O Viết CTHH của hợp chất

Các câu hỏi liên quan

A. Fill in Past Simple, Past Continuous or Past Perfect. 1. John ……………………..……..(play) with the children after he …………………….(have) dinner. 2. The farmer …………………………..(harvest) the apples before he …………………………..(take) them to his neighbour to make cider. 3. After it ……………………….(stop) raining the tennis match ……………..…………….(can) start. 4. After George ………..………….(swallow) his medicine he …………..……..(begin) to feel much better. 5. Before he ……………………..(become) president he ……………….…………(work) as an actor. 6. The tourists ………………………….(jump) into the pool as soon as they ……………..(unpack) their suitcases. 7. They …………………(sell) their flat before they ….………………….(move) to the Netherlands. 8. He ………………..……….(work) as a tourist agent after he ………………………..(finish) school. 9. After he ………………….………….(call) the police he ………………………..(call) the ambulance. 10. We ………………..……….(leave) the cinema as soon as the movie ……………………….(end). 11. After Mary ……..….….(get) her new school uniform she ………….(show) it to her parents. 12. He ……………...….(see) the robbers after they ……..………………………….(leave) the bank. 13. When we …………….…………(arrive) at the church the ceremony ……………………………….. (already start). 14. She ………………………….(need) help because someone ……………………(steal) her money. 15. She …………………………………(do) her homework before she ……………………….(visit) me.