属于氧化还原反应的是（ ）
A．CaCO3 ="=" CaO + CO2 ↑
B．NH3+ HCl = NH4Cl
C．NaOH + HCl =" NaCl" +H2O
D．Zn + H2SO4（稀）= ZnSO4 +H2
答案：D
A 、B、C没有化合价的变化，是非氧化还原反应
D 有单质参加，有单质生成，即有化合价的变化，是氧化还原反应。选D。
| 从方框中选择最佳选项完成对话，有两项多余。 | |
B: Yes. 1._____ A: I want to know if you send take-away food. B: Sure. A: I'd like to order something for my lunch. B: 2._____ A: I'd like to have beef with potatoes and a hot dog. B: OK. 3._____ A: No, thanks. How can I pay you? B: 4._____ By the way, what time do you want your lunch? A: Around 11: 30 am. B: 5._____ A: Oh, yeah. Room 502 in Garden Building. B: OK. Thank you. See you then. |
| 阅读理解。 根据短文内容 ，从短文后的选项中选出能填入空白处的最佳答案，选项中有两项为 多余选项。 | |
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