How would set up a problem like this?

A mass of 20.0 g of NaOH is dissolved in water to form 5.0 dm^3 of solution. What is the molarity of the hydrogen ion concentration if the temperature is 25 degrees Celsius?

2 answers

M = #moles/dm^3
moles = grams/molar mass
Solve for moles.
Substitute moles and dm^3 to find M. Then
pOH = -log(OH^-) and solve for pOH.
Then pOH + pH = 14 and solve for pH.
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