(1)n(O2)==0.003mol, 2(CaO2?xH2O)2CaO+O2↑+2xH2O 2mol 1mol n(CaO2?xH2O) 0.003mol n(CaO2?xH2O)=0.006mol, 则n(CaO2)=n(CaO2?xH2O)=0.006mol, 故答案为:0.006mol; (2)n(CaCO3)==0.007mol, ①根据Ca元素守恒,可知:n(CaO)=0.007mol-0.006mol=0.001mol, m(CaO)=0.001mol×56g/mol=0.056g, 答:样品中CaO的质量为0.056g; ②样品中水的质量为:m(H2O)=0.542g-m(CaO2)-m(CaO)=0.542g-0.006mol×72g/mol-0.056g=0.054g, n(H2O)==0.003mol, x===0.5, 答:样品中CaO2?xH2O的x值为0.5. |