A:0.1000 mol·L−1 H2C2O4溶液:c(H+ ) =0.1000 mol·L−1+c(C2O42− )+c(OH−)−c(H2C2O4 )
B:c(Na+ ) =c(总)的溶液:c(Na+ ) >c(H2C2O4 ) >c(C2O42− ) >c(H+ )
C:pH = 7的溶液:c(Na+ ) =0.1000 mol·L−1+ c(C2O42−) −c(H2C2O4)
D:c(Na+ ) =2c(总)的溶液:c(OH−) −c(H+) = 2c(H2C2O4) +c(HC2O4−)