Question

Calculate ph of solution labelled 2.6 M NaOH?

Answer 1

`color(blue)"pH = 14.415"`

Explanation:

Sodium hydroxide and Water is an exothermic reaction (heat generation):

`NaOH(s) + H_2O(l)` `=>` `Na^+` + `OH^-` + `H_2 O` + HEAT

NaOH is a strong base and it is dissociate completely into Na+ and OH-.

DATA
[OH-] = 2.6 M
[H+] = Unknown

PURPOSE
Determine pOH
Calculate pH using equation: pH + pOH = 14

`pOH = -log [2.6]`
pOH = - 0.415

pH - 0.415 = 14

`color(blue)"pH = 14.415"`

A strong base has a high pH (>7).

NOTE:
pH is outside of the normal 1-14 range due to its concentration exceeds the maximum value of the previous pH-range of 1M.