10mlPH=4的盐酸,稀释10倍到100ml时,PH=?
问题描述：
10mlPH=4的盐酸,稀释10倍到100ml时,PH=?
答
稀释前
pH = 4,则c(H+) = 10^-4mol/L,
n(H+) = c(H+)xV = 10^-4mol/Lx(10/1000)L= 10^-6mol
稀释后
n(H+)= 10^-6mol
c(H+) = n(H+)/V = 10^-6mol/(100/1000)L = 10^-5mol/L
所以稀释后,pH = 5