Question

A bottle of commercial H2SO4 density 1.787g/ml is labelled as 86% by weight. What is the molaritiy of the solution and what volume of the acid has to be used to make 1l of 0.2M H2SO4

Answer 1

Hence the molarity will be 1.7M and Volume will be 0.82L

Answer 2

Answer : The molarity of solution is 15.71 M and the volume of acid required is 0.013 L.

Solution : Given,

86 g of  $H_2SO_4$ is present in 100 g of the solution.

Molar mass of $H_2SO_4$ = 98 g/mole

$Moles=\frac{\text{Given mass}}{\text{Molar mass}}$

$Moles=\frac{86g}{98g/mol}=0.88moles$

Mass of solution = 100 g

Now we have to calculate the volume of solution.

$Volume=\frac{Mass}{Density}=\frac{100g}{1.787g/ml}=56ml$  

Molarity : It is defined as the number of moles of solute present in one liter of solution.

Formula used :

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

where,

n = moles of solute $H_2SO_4$ = 0.88 moles

$V_s$ = volume of solution in liter  = 0.05596L

Now put all the given values in the formula of molarity, we get

$Molarity=\frac{0.88moles}{0.056L}=15.71 mole/L$

Therefore, the molarity of solution will be 15.71 M.

2) $M_1V_1=M_2V_2$

$15.71M\times V_1=0.2\times 1L$

$V_1=0.013L$