Chem: Calculate volume given molarity and pH

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To calculate the volume of solution needed to dissolve 1.0 mol of KOH for a pH of 12.5, the concentration of hydronium ions is first determined as 3.2 x 10^-13 mol/L. This leads to a hydroxide ion concentration of 3.1 x 10^-2 M. Using the formula for molarity, the required volume is calculated as 32 liters. The user expresses uncertainty about the correctness of this solution. The final answer is confirmed as 32 L, despite the user's doubts.
Winning
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Homework Statement



What volume of solution is needed to dissolve 1.0 mol of a strong base such as KOH to make a solution whose pH is 12.5?

Homework Equations



KOH_{(s)} \rightarrow K^{+}_{(aq)} + OH^{-}_{(aq)}

pH = -log[H_{3}O^{+}]

The Attempt at a Solution



I'm not going to bother with the pretty print here... sorry

12.5 = -log[H3O+]
[H3O+] = 10^-12.5
[H3O+] = 3.2 x 10^-13 mol/L

[OH-] = 10^-14/(3.2 x 10^-13) M
[OH-] = 3.1 x 10^-2 M

1.0 mol * 1 L / (3.1 x 10^-2) mol = 32 L

ans: 32 L

I feel like I'm wrong... help please.
 
Last edited:
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Winning said:
I feel like I'm wrong...

You feel wrong.
 

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