Answer:
[tex]m = 1\,g[/tex]
Explanation:
The molarity is the ratio of the amount of moles solvent to volume of the solute.
[tex]0.010\,M = \frac{0.010\,moles\,NaOH}{1\,L}[/tex]
The quantity of solute is determined by simple rule of three:
[tex]n = \left(\frac{2.5\,L}{1\,L} \right)\cdot (0.010\,mole)[/tex]
[tex]n = 0.025\,moles[/tex]
The molecular weight of NaOH is [tex]39.997\,\frac{g}{mole}[/tex], the mass of solute is:
[tex]m = 1\,g[/tex]