Answer:
mass = 0.2982 grams
Explanation:
Given that;
volume = 100.0 mL = 0.1 L
Molarity =0.040 M
Since Molarity = [tex]\frac{no of moles }{volume}[/tex]
[tex]0.040 M = \frac{x}{0.1}[/tex]
(x) no of moles = 0.040 × 0.1
= 0.004 moles
Also; to calculate the mass of KCl should you weigh to make this solution;
we have;
no of moles =[tex]\frac{mass}{molar mass}[/tex]
molar mass of KCl = 74.55 g/mol
∴
0.004 moles = [tex]\frac{mass}{74.55g/mol}[/tex]
mass = 0.004 moles * 74.55 [tex]\frac{g}{mol}[/tex]
mass = 0.2982 grams
Hence, the mass of KCl should you weigh to make this solution is 0.2982 grams
