Question

In a mixture of gases the volume content of a gas is 0.06% at STP. Calculate no. of molecules of gas in 1Litre of mixture

Answer 1

Answer:- $1.61*10^1^9molecules$

Solution:- As per the given information, the gas is 0.06% by volume at STP and the total volume of the gas mixture is 1 Liter. Let's calculate the volume of the gas in the mixture as:

gas volume = $\frac{0.06*1L}{100}$  = 0.0006 L

We know that, at STP, the volume of 1 mol of a gas is 22.4 L. Using this information we could calculate the moles of the gas in it's 0.0006 Liters as:

$\frac{0.0006L*1mol}{22.4L}$

= 0.0000268 mol

Finally, the moles are converted to molecules using Avogadro number.

1 mol = $6.02*10^2^3molecules$

So, $\frac{0.0000268mol*6.02*10^2^3molecules}{1mol}$

= $1.61*10^1^9molecules$

Hence, at STP, there would be $1.61*10^1^9molecules$ of the gas present in the gas mixture.