题目

下列除杂试剂选用正确且除杂过程不涉及氧化还原反应的是 物质（括号内为杂质）除杂试剂AFeCl2溶液（FeCl3）Fe粉BNaCl溶液（MgCl2）NaOH溶液、稀HClCCl2（HCl）H2O、浓H2SO4DNO（NO2）H2O、无水CaCl2 A. A B. B C. C D. D 答案：【答案】B【解析】发生的反应中，存在元素的化合价变化，与氧化还原反应有关；反之，不存在元素的化合价变化，则与氧化还原反应无关，以此解答该题。A.FeCl3与Fe反应生成FeCl2，2FeCl3+Fe=2FeCl2，此过程中Fe的化合价发生变化，涉及到了氧化还原法应，故A不符合题意；B.MgCl2与NaOH溶液发生复分解反应MgCl根据对话内容，从对话后的选项中选出能填入空白处的最佳选项，并将答案标号填写在本题下面相应题号后的横线上。选项中有两项多余选项。—Now, tell me about the man who stole your neighbor’s car. What did he look like?—Well, sir. He was tall…—     1    —Oh yes, and he was younger than you — only about thirty, I’d say.—Well! And what color was his hair?—It was brown, and short… it was similar to yours, actually.—      2    —No, He was clean-shaven.—OK. Now have a look at these photos — can you see him?—     3    —But that’s Frankie Famham — he’s got a beard, and he’s very short!—Hm, well…—    4    —Yes, the strangest thing was that he appeared to be a gentleman — he was wearing a suit… not like a thief at all.—Hm, like this photo?—Yes, that’s him!—That’s Bill Mahony: he’s in prison! Are you sure you saw the thief?—     5    A. No, I can’t.B. Taller than me?C. How tall was he?D. Did he have a beard?E. Well, er, it was very dark…F. Oh yes, he looked exactly like this one here.G. Do you remember anything else about the man?