问题
选择题
下列除杂的实验过程都正确的是（括号内为杂质）（ ）
A．待提纯物：H2（H2O），选用试剂：浓硫酸，操作方法：洗气
B．待提纯物：KCl（K2CO3），选用试剂：稀硫酸，操作方法：蒸发、结晶
C．待提纯物：CO2（HCl），选用试剂：氢氧化钠溶液，操作方法：洗气
D．待提纯物：CuO（Cu），选用试剂：稀硫酸，操作方法：过滤、洗涤、干燥
答案
答案：A
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下列除杂的实验过程都正确的是（括号内为杂质）（ ）
A．待提纯物：H2（H2O），选用试剂：浓硫酸，操作方法：洗气
B．待提纯物：KCl（K2CO3），选用试剂：稀硫酸，操作方法：蒸发、结晶
C．待提纯物：CO2（HCl），选用试剂：氢氧化钠溶液，操作方法：洗气
D．待提纯物：CuO（Cu），选用试剂：稀硫酸，操作方法：过滤、洗涤、干燥
答案：A
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