Question

10g of H2SO4 has been dissolved in excess of water to dissociate it completely into ions.calculate the number of molecules in 10g of H2SO4 and number of positive ions?​

Answer 1

Explanation:

The answer is in the picture

Answer 2

Answer: $10g$ of $H$₂$SO$₄ has been dissolved in excess water to dissociate it completely into ions. So $6.14$×$10^{22}$ is the total number of molecules and $1.23$×$10^{23}$ is the total number of positive ions.

Explanation:

Given,

weight of $H$₂$SO$₄ = 10g

Number of moles = $\frac{Given weight}{Molecular weight}$

The molecular weight of $H$₂$SO$₄ = $98g/mol$

The number of moles of $H$₂$SO$₄ =  $\frac{10g}{98g/mol}$ = $0.102 mols$

The total no of molecules in one mole of a substance can be calculated by the formula = $N_{A}$× no of moles

So the total no of molecules in 10g $H$₂$SO$₄ = $0.102$ × $6.022$×$10^{23}$ = $6.14$×$10^{22}$

In water, $H$₂$SO$₄ dissociate as $2 H$⁺ and $SO$₄²⁻ .

So in one mole of $H$₂$SO$₄, there will be $2H^{+}$

The total no of positive ions = $2$× $6.14$×$10^{22}$ = $1.23$×$10^{23}$