Answer
(a) $[OH^-] = 1.8 \times 10^{- 10}M$
(b) $[OH^-] = 3.4 \times 10^{- 2}M$
(c) $[OH^-] = 3.2 \times 10^{- 13}M$
(d) $[OH^-] = 1.8 \times 10^{- 6}M$
Work Step by Step
1. Calculate the hydroxide ion concentration:
pH + pOH = 14
4.25 + pOH = 14
pOH = 9.75
$[OH^-] = 10^{-pOH}$
$[OH^-] = 10^{- 9.75}$
$[OH^-] = 1.8 \times 10^{- 10}M$
2. Calculate the hydroxide ion concentration:
pH + pOH = 14
12.53 + pOH = 14
pOH = 1.47
$[OH^-] = 10^{-pOH}$
$[OH^-] = 10^{- 1.47}$
$[OH^-] = 3.4 \times 10^{- 2}M$
3. Calculate the hydroxide ion concentration:
pH + pOH = 14
1.5 + pOH = 14
pOH = 12.5
$[OH^-] = 10^{-pOH}$
$[OH^-] = 10^{- 12.5}$
$[OH^-] = 3.2 \times 10^{- 13}M$
4. Calculate the hydroxide ion concentration:
pH + pOH = 14
8.25 + pOH = 14
pOH = 5.75
$[OH^-] = 10^{-pOH}$
$[OH^-] = 10^{- 5.75}$
$[OH^-] = 1.8 \times 10^{- 6}M$