硼砂Na2B4O7·10H2O,摩尔质量=381.37克/摩尔Na2B4O7·10H2O+2HCl=2NaCl+4H3BO3+5H2O381.37克-----------2摩尔0.5635克----------(25.78X/1000),X=0.1146摩尔/升
盐酸的浓度c=0.5635÷381.4÷(25.78÷1000)=0.0573mol/L