表2 五種標(biāo)準(zhǔn)溶液的pH(S)值*
T/C |
A |
B |
C |
D |
E |
0 5 10 15 20 25 30 35 38 40 45 50 55 60 70 80 90 95 |
3.557 3.552 3.548 3.548 3.547 3.547 3.542 3.554 3.560 3.580 3.609 3.650 3.674 |
4.003 3.999 3.998 3.999 4.002 4.008 4.015 4.024 4.030 4.035 4.047 4.060 4.075 4.091 4.126 4.164 4.205 4.227 |
6.984 6.951 6.923 6.900 6.881 6.865 6.853 6.844 6.840 6.838 6.834 6.833 6.834 6.836 6.845 6.859 6.877 6.886 |
7.534 7.500 7.472 7.448 7.429 7.413 7.400 7.389 7.384 7.380 7.373 7.367 |
9.464 9.395 9.332 9.276 9.225 9.180 9.139 9.102 9.081 9.068 9.038 9.011 8.985 8.962 8.921 8.885 8.850 8.833 |
這些標(biāo)淮溶液的組成是:
A:酒石酸氫鉀(25℃飽和)
B:鄰苯二甲酸氫鉀,m=0.05nolkg-1
C:磷酸二氫鉀,m=0.025molkg—1
D:磷酸氫二鈉,m=0.025molkg-l
D:磷酸二氫鉀,m=0.008695molkg-1
磷酸氫二鈉,m=0.03043molkg-1
E:硼砂,m=0.01molkg-1
這里m表示溶質(zhì)的質(zhì)量摩爾濃度,溶劑是水。