Question

A solution of HCl is .3M. Determine what mass of acid has been dissolved in 150 mL of solution

Answer 1

1.643 g mass of acid has been dissolved

Further explanation

Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution

$\large \boxed {\bold {M ~ = ~ \dfrac {n} {V}}}$

Where

M = Molarity

n = number of moles of solute

V = Volume of solution

Molarity of HCl solution = 0.3 M

Volume of HCl solution = 150 ml=0.15 L

So moles of HCl :

$\tt n=M\times V\\\\n=0.3\times 0.15\\\\n=0.045$

mass of HCl (MW=36.5 g/mol) :

$\tt mass=moles\times MW\\\\mass=0.045\times 36.5\\\\mass=1.643~g$