Question

Calculate the number of molecules in 3.4g of h2s

Answer 1

molecular mass of H2S is 34 g/mol

no. of moles = given mass / molecular mass
= 3.4÷34
= 0.1 moles
1 mole contains 6.022 *10^23 molecules
then, 0.1 moles contains
= 6.022*10^23 * 0.1
= 6.022 *10^22 molecules



hope u understand it...

Answer 2

Answer:

The number of molecules in 3.4 g of $H^2S$ is $6.022\times 10^{22}$

Step-by-step explanation:

Given : 3.4 g of $H^2S$

To find : Calculate the number of molecules?

Solution :

We know the molecular mass of $H^2S$ is 34 g/mol.

First we find the number of moles in $H^2S$

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molecular mass}}$

$\text{Number of moles}=\frac{3.4}{34}$

$\text{Number of moles}=0.1$

In $H^2S$ there is 0.1 moles.

We know, $1\text{ mole}=6.022\times 10^{23}\text{ molecules}$

So, $0.1\text{ mole}=6.022\times 10^{23}\times 0.1\text{ molecules}$

$0.1\text{ mole}=6.022\times 10^{22}\text{ molecules}$

Therefore, The number of molecules in 3.4 g of $H^2S$ is $6.022\times 10^{22}$