急,急,0.1mol/L磷酸一氢钠的PH是多少啊?

问题描述:

急,急,0.1mol/L磷酸一氢钠的PH是多少啊?

c = 0.1 (mol/L) Na2HPO4溶液的PH值计算:Ka2=6.3*10^-8 ; Ka3=4.4*10^-13[H+] = √ [ Ka2 (Ka3 * c +Kw) / ( Ka2 + c) ] 因为:Ka3 * c <20 Kw,Kw不可忽略;但 Ka2 + c ≈ c [H+] = √ [ Ka2 (Ka3 * c +Kw) / c)...