Molarity (mol/L) is the ratio between the amount of substance in the solute (n) and the volume of the solution in liters (V).
The formula is M = n/V.
First, we need to transform 50 grams of NaOH into moles.
We need to use the molar mass of NaOH, which is 40 g/mol.
40 g --- 1 mol
50 g --- x mol
40x = 50
x = 50/40
x = 1.5 moles
So:
M = 1.25/5
M = 0.25 mol/L
Answer: M = 0.25 mol/L