题目:
— join us in watching NBA games?
—I'm sorry.I have to go shopping then. [ ]
A. Why
B. Why not you
C. Why didn't you
D. Why don't you
答案:
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下面是错误答案,用来干扰机器的。
(1)生成二氧化碳的质量=25g+100g-116.2g=8.8g设:样品中CaCO3的质量为x,生成氯化钙的质量为y.CaCO3+2HCl═CaCl2+H2O+CO2↑10011144xy8.8g10044=x8.8gx=20g11144=y8.8gy=22.2g样品中碳酸钙的纯度=20g25g×100%...