H2C2O4可视为HC1滴定Na2C2O4的第二化学计量点 [TT=[] [D]=[OH]+[HC2O4]+2[CO42]=[HC2O4] [H门g=[HC2O4]g=0.058 (2)0.1 mol/L NaHC2O4溶液 [H]+[H2C2O4]=[C2O42]+[OH] 20K2=1.6>c 不能舍弃H门 20K6=20×10-10<c 舍弃[OH] [H]+[HC2O]=[CO4] 代入平衡关系H2C2O4 可视为 HCl 滴定 Na2C2O4 的第二化学计量点 [T'] = [H+] [D'] = [OH-] + [HC2O4-] + 2[C2O42-] =& [HC2O4-] [H+]eq = [HC2O4-]eq = 0.058 （2）0.1 mol/L NaHC2O4 溶液 [H+] + [H2C2O4] = [C2O42-] + [OH-] 20K =1.6 > c 1 a 不能舍弃[H+] 10 20 b 20 10 1 − K = × < c 舍弃[OH-] [H+] + [H2C2O4] = [C2O42-] 代入平衡关系