1/5单选题
难度：
1.给45克铜和氧化铜的混合物通入一会氢气后，加热至完全反应，冷却称量固体质量为37克，求原混合物中铜元素的质量分数？
| A | 85.2% |
| B | 84.2% |
| C | 83.2% |
| D | 82.2% |
- 提示1：
- IOeUseaWueeoi+W8j+WPr+efpeWbuuS9k+i0qOmHj+eahOWHj+WwkemHj+WwseaYr+WkseWOu+eahOawp+eahOi0qOmHj++8jOaJgOS7peawp+WFg+e0oOeahOi0qOmHj+S4ujQ1Zy0zN2c9OGc=
- 提示2：
- IOa3t+WQiOeJqeS4remTnOWFg+e0oOi0qOmHj+S4uu+8mjQ1Zy04Zz0zN2c=
- 提示3：
- IOmTnOWFg+e0oOi0qOmHj+S4ujM3Zy80NWfDlzEwMCU9ODIuMiU=
正确答案：RA==
6Kej77ya55Sx5pa556iL5byP5Y+v55+l5Zu65L2T6LSo6YeP55qE5YeP5bCR6YeP5bCx5piv5aSx5Y6755qE5rCn55qE6LSo6YeP77yM5omA5Lul5rCn5YWD57Sg55qE6LSo6YeP5Li6NDVnLTM3Zz04Z++8jOaJgOS7pea3t+WQiOeJqeS4remTnOWFg+e0oOi0qOmHj+S4uu+8mjQ1Zy04Zz0zN2fvvIzmiYDku6Xpk5zlhYPntKDotKjph4/kuLozN2cvNDVnw5cxMDAlPTgyLjIlPGJyPuaVheetlOahiOS4uu+8mjgyLjIl
2/5单选题
难度：
2.已知同一状态下，气体分子间的分子个数比等于气体间的体积比。把30mL甲烷和氧气的混合气体点燃，冷却至常温，测得气体的体积为16mL，则原混合气体中甲烷和氧气的体积比？
| A | 1：4 |
| B | 7：23 |
| C | 1：3 |
| D | 7：22 |
- 提示1：
- IOagueaNrumimOebruS/oeaBr+WPr+efpe+8jOeUsueDt+WSjOawp+awlOeUn+aIkOS6jOawp+WMlueis+WSjOawtO+8jOW4uOa4qeS4i+awtOS4uua2suaAge+8jOacgOWQjuawlOS9k+eahOS9k+enrzE2bUzvvIzmsJTkvZPnmoTkvZPnp6/lh4/lsJHkuobvvIzmoLnmja7ljJblrabmlrnnqIvlvI/mib7lh7rlj5jljJbph4/kuI7lkITkuKrph4/kuYvpl7TnmoTlhbPns7vvvIzku6PlhaXmlbDmja7ov5vooYzorqHnrpfjgII=
正确答案：Qg==
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
3/5单选题
难度：
3.
研究性学习小组为了测定黄铜（铜、锌合金）的组成，用电子天平分别称得锥形瓶与棉花的质量为44.1g，称取黄铜样品20.0g。在锥形瓶中加入该样品和足量稀硫酸后瓶口塞上棉花，如图1所示。将电子天平称量的数据绘成下图2。
图1 图2
按图计算：恰好反应时所得溶液中生成物的质量分数。
| A | 10% |
| B | 15% |
| C | 20% |
| D | 25% |
- 提示1：
- PHA+5Zug5Li66ZOc5LiN5LiO56iA56Gr6YW45Y+N5bqU77yM6buE6ZOc5Lit5Y+q5pyJ6ZSM5LiO56iA56Gr6YW45Y+N5bqULiDmurbmtrLnmoTotKjph4/pmo/nnYDlj43lupTnmoTov5vooYzogIzlj5jljJbvvJvnlJ/miJDmsKLmsJTnmoTotKjph4/moLnmja7lm74y5Y+v6K6h566X5Ye65p2l77yb54S25ZCO5a+554Wn6YCJ6aG56L+b6KGM5YiG5p6Q5Y2z5Y+v77ybPC9wPg==
- 提示2：
- PHA+5Yip55So6ZSM5LiO56Gr6YW45Y+N5bqU55qE5YyW5a2m5pa556iL5byP5ZKM55Sf5oiQ5rCi5rCU55qE6LSo6YeP77yM5YiX5Ye65q+U5L6L5byP77yM5bCx5Y+v6K6h566X5Ye65qC35ZOB5Lit6ZSM55qE6LSo6YeP5ZKM55Sf5oiQ55qE56Gr6YW46ZSM55qE6LSo6YePOzwvcD4=
正确答案：Qw==
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
4/5单选题
难度：
4.
已知同一状态下，气体分子间的分子个数比等于气体间的体积比。现有CO、O2、CO2混合气体9ml，点火爆炸后恢复到原来状态时，体积减少1ml，通过氢氧化钠溶液后，体积又减少5ml，假设剩余气体为氧气，则原混和气体中CO、O2、CO2的体积比？
| A | 2:4:3 |
| B | 5:1:3 |
| C | 5:4:3 |
| D | 2:1:3 |
- 提示1：
- PHA+6YCa6L+H5pa556iL5byP5qC55o2u5L2T56ev55qE5YeP5bCR6K6h566X5Ye65Y+C5Yqg5Y+N5bqU55qE5LiA5rCn5YyW56Kz44CB5rCn5rCU44CB55Sf5oiQ55qE5LqM5rCn5YyW56Kz55qE5L2T56ev44CCPC9wPg==
正确答案：QQ==
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
5/5多选题
难度：
5.
有5.85克NaCl样品（其中有少量下列某盐），当它跟足量的硝酸银溶液充分反应，得到14.4克氯化银沉淀，则可能混有的盐
| A | CaCl2 |
| B | KCl |
| C | BaCl2 |
| D | MgCl2 |
- 提示1：
- PHA+5YWI5YGH6K6+NS44NWfmoLflk4Hlhajpg6jmmK/msK/ljJbpkqA8aT7vvIw8L2k+5qC55o2u5YyW5a2m5pa556iL5byP6K6h566X5Ye655Sf5oiQ5rKJ5reA55qE6LSo6YeP77yM5aaC5p6c5a6e6ZmF55Sf5oiQ55qE5rKJ5reA6LSo6YeP77ye5YGH6K6+NS44NWflhajpg6jmmK/msK/ljJbpkqDml7bnlJ/miJDnmoTmsonmt4DotKjph4/vvIzliJnor7TmmI7mnYLotKjnianotKjkuK3msK/lhYPntKDnmoTotKjph4/liIbmlbDopoHlpKfkuo7msK/ljJbpkqDkuK3msK/lhYPntKDnmoTotKjph4/liIbmlbAuPC9wPg==
正确答案：QSxE
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