Question

0 31/80 The molarity of an HCl solution is 1 M. Calculate the
molality of the solution if the density of the solution obtained
is 1036.5 g/L.​

Answer 1

Answer: 0.96 m

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

$Molarity=\frac{n\times 1000}{V_s}$

where,

n= moles of solute

 $V_s$ = volume of solution in ml

Molality of a solution is defined as the number of moles of solute dissolved per kg of the solvent.

$Molarity=\frac{n\times 1000}{W_s}$

where,

n = moles of solute

 $W_s$ = weight of solvent in g

Molarity of an $HCl$ solution is 1 M.  i.e. 1 mole of $HCl$ is present in 1 L of solution

Moles of solute  = 1

Density of solution = 1036.5 g/L

Mass of solution =$Density\times {\text {Volume of solution}}=1036.5g/L\times 1L=1036.5g$

$Molality= \frac{1\times 1000}{1036.5g}=0.96$

Thus molality of the solution is 0.96 m.