pH from hydroxide concentration
An aqueous solution at 25 °C has [OH⁻] = 1 × 10⁻⁴ M. What is its pH?
Answer C: explanation for every choice
A
4 is the pOH, not the pH.
B
7 is neutral, where [OH⁻] = 10⁻⁷ M.
C
Correct. pOH = 4, so pH = 14 − 4 = 10.
D
This would require [OH⁻] = 1 M.
TakeawaypH + pOH = 14 at 25 °C.
Equation usedpH and pOH
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