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【简答题】
化学计量在化学中占有重要地位，请回答下列问题： （1）0.3molNH 3 分子中所含原子数与______个H 2 O分子中所含原子数相等． （2）含0.4molA1 3+ 的Al 2 （SO 4 ） 3 中所含的SO 4 2- 的物质的量是______． （3）已知16gA和20gB恰好完全反应生成0.04molC和31.76gD，则C的摩尔质量为______． （4）在一定的温度和压强下，1体积气体X 2 跟3体积气体Y 2 化合生成2体积化合物，则该化合物的化学式是______． （5）某盐混合溶液中含有离子：Na + 、Mg 2+ 、Cl - 、SO 4 2- ，测得Na + 、Mg 2+ 和Cl - 的物质的量浓度依次为：0.2mol?L -1 、0.25mol?L -1 、0.4mol?L -1 ，则c（SO 4 2- ）=______．
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A.
twice as much as
B.
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C.
twice more than
D.
twice as more as
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A.
helping
B.
helped
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it helps
D.
will help
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B.
心理过程是否具有完整性和协调性
C.
思维过程是否具有完整性和逻辑性
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人格心理特征是否具有相对稳定性
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before
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A.
不必再出卖自己劳动力的自由
B.
支配生产资料的自由
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不受雇主雇佣剥削的自由
D.
选择受雇于某个雇主的自由
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