Ezek mind erős savak/bázisok:

a, pH = -lg`[H^+]` = -lg`1.93*10^(-4)` = 3,71

pOH = 14-pH = 14-3,71 = 10,29


b, pH = -lg`[H^+]` = -lg`3.48*10^(-9)` = 8,46

pOH = 14-pH = 14-8,46 = 5,54


c,

`HClO_4` `rightarrow` `H^+` + `ClO_4`

`M_(HClO_4)` = 100,5 `g/(mol)`

1 `dm^3` oldatban van 10,72 g perklórsav, ami `10.72/100.5` = 0,107 mol

pH = -lg`[H^+]` = -lg 0,107 = 0,972

pOH = 14-pH = 14-0,972 = 13,028


d,

HBr `rightarrow` `H^+` + `Br^-`

pH = -lg`[H^+]` = -lg 0,0278 = 1,556

pOH = 14-pH = 14-1,556 = 12,444

e,

KOH `rightarrow` `K^+` + `OH^-`

`M_(KOH)` = 56 `g/(mol)`

1 `dm^3` oldatban van 1,808 g KOH, ami `1.808/56` = `3.23*10^(-2)` mol

pOH = -lg`[OH^-]` = -lg`3.23*10^(-2)` = 1,491

pH = 14-pOH = 14-1,491 = 12,509


f,

`Ca(OH)_2` `rightarrow` `Ca^(2+)` + 2 `OH^-`

`c_(Ca(OH)_2)` = `3.25*10^(-2)`; `[OH^-]` = `2*3.25*10^(-2)` = `6.5*10^(-2)`

pOH = -lg`[OH^-]` = -lg`6.5*10^(-2)` = 1,187

pH = 14-pOH = 14-1,187 = 12,813