Question

Calculate the amount of 2litres of m/10 HCL present in the following solutions

Answer 1

Answer:

$2$ liters of  $\frac{M}{10}$  HCl solution contains $7.3$ g of HCl·

Explanation:

Given that,

The volume of HCl solution taken $=$ $2$ L

The concentration of HCl solution  $=$ $\frac{M}{10}$

Here, M denotes the term molarity which defines the concentration of a solution·

$\frac{M}{10}$  HCl solution means $0.1$ molar concentration of HCl solution·

       To find out the amount of HCl present in $2$ L of  $\frac{M}{10}$  HCl solution first, we need to calculate the number of moles of HCl present in  $2$ L of  $\frac{M}{10}$  HCl solution· It can be found out from the molarity equation·

So, the equation for the molarity is,

M  $=\ \ \frac{No.\ Of.\ Moles\ Of\ Solute}{Volume\ Of\ Solution\ In\ Litre}$

Here,

Molarity  $=$  $0.1$ M

The volume of the solution $=$  $2$ L

On substituting the values we get,

 ⇒  No of moles   $=$ Molarity ×  volume of the solution

 ⇒  No of moles   $=$ $0.1$ × $2$

That is,

  ⇒  No of moles  $=$  $0.2$ moles of HCl·

Therefore,

$2$ L of  $\frac{M}{10}$  HCl solution contains $0.2$ moles of HCl·

We know that,

$1$ mol of HCl solution weighs $36.5$ g of HCl which is the atomic mass of HCl·

Therefore,

$0.2$ moles of HCl weighs $\frac{0.2\ mol\ *\ 36.5\ g}{1\ mol}$

That is,

 ⇒  $7.3$ g of HCl·

Hence,

$2$ L of  $\frac{M}{10}$  HCl solution contains $7.3$ g of HCl·