精密称取硼砂基准物0.8714g,用HCL溶液滴定，终点时消耗HCL溶液21.12ML，

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已知：硼砂（Na2B4O7.10H2O)摩尔质量M=381.42g/mol m=0.8714g V=21.12ml1）计算盐酸溶液的浓度：假设盐酸溶液的浓度是C（HC1)滴定反应：Na2B4O7 + 2HC1 + 5H2O = 2NaC1 + 4H3BO31 2m/M C(HC1)*V/1000m/M=(1/2)*C(HC1)*V/10000.8714/381.42=(1/2)*C(HC1)*21.12/1000C(HC1)=0.2163mol/L2）计算氢氧化钠溶液的浓度C(NaOH)：C(HC1)*V(HC1)=C(NaOH)*V(NaOH)C(NaOH)=C(HC1)*V(HC1)/V(NaOH)=0.2163*1.025=0.2218mol/L