Question

What mass of NaOH must be used to prepare 2.5 L of a 0.010 M solution

Answer 1

Answer:

$m = 1\,g$

Explanation:

The molarity is the ratio of the amount of moles solvent to volume of the solute.

$0.010\,M = \frac{0.010\,moles\,NaOH}{1\,L}$

The quantity of solute is determined by simple rule of three:

$n = \left(\frac{2.5\,L}{1\,L} \right)\cdot (0.010\,mole)$

$n = 0.025\,moles$

The molecular weight of NaOH is $39.997\,\frac{g}{mole}$, the mass of solute is:

$m = 1\,g$