Question

What would be the resulting molaritybof a solution made by dissolving 17.8 g of LiF in enough water to make a 915-millimeter solution?

Answer 1

Answer: Molarity of solution is 0.751 M. 

Reason:
Given: weight of solute (LiF) = 17.8 g, volume of solution = 915 ml = 0.915 l

We know that,
Molarity = $\frac{\text{weight of solute (g)}}{\text{Molecular weight X Volume of solution(l)}}$

Molecular Weight of LiF = 25.9 g/mol. 

∴, Molarity = $\frac{17.8}{25.9X0.915}$
                 = 0.751 M

Answer 2

Answer:

0.751 M

Explanation:

Given:

Mass of LiF (solute), m = 17.8 g

Volume of water (solvent), V = 915 ml = 0.915 L

Formula:

Molar mass of LiF = 25.9 g/mol

$Molarity = \frac{moles of solute}{Volume of solution}$

$Moles LiF= \frac{Mass}{Molar Mass} = \frac{17.8 g}{25.9 g/mol} = 0.6873 moles$

$Molarity = \frac{0.6873 moles}{0.915 L} = 0.751 moles/L$