已知:硼砂(Na2B4O7.10H2O)摩尔质量M=381.42g/mol m=0.8714g V=21.12ml
1)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 + 4H3BO3
1 2
m/M C(HC1)*V/1000
m/M=(1/2)*C(HC1)*V/1000
0.8714/381.42=(1/2)*C(HC1)*21.12/1000
C(HC1)=0.2163mol/L
2)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