Question

Pure hydrogen sulphide is stored in a tank of 100 litre capacity at $20{}^\circ C$ and 2 atm pressure. The mass of the gas will be:
A. 34 g
B. 340 g
C. 282.68 g
D. 28.24 g

Answer 1

Hint: In reality ideal gas does not exist it is just a hypothetical gas which is proposed to simplify the equations. It is made up with a set of randomly moving point particles which interact only through elastic collisions and there is no loss of kinetic energy during collision.

Complete answer:
If we take one mole sample of any gas and put them in a container and maintain a constant temperature and pressure and lower the density then at really lower densities all the real gases tend to obey the universal law which is known as ideal gas law. This law describes an equation which is known as ideal gas equation and this equation is given by the equation:
$PV=nRT$
Where P = Pressure, V = Volume, n = number of moles, R = Gas constant and T = Absolute temperature.
$n=\dfrac{PV}{RT}$, P = 2 atm, V = 100 L, R = 0.0821 and T = 293 K by putting the values in the equation n will be equal to 8.31 mol, where
Number of moles of gas can be calculated by given mass of the gas divided by its molar mass whose equation can be given by:
$n=\dfrac{m}{M}$
Molar mass of hydrogen sulphide is 34 g so we can calculate mass used by:
$M=m\times n=8.31\times 34=282.54g$

Hence option C is the correct answer.

Note:
Ideal gas law also suffers from the serious limitation that equations hold only in that condition when the density is low. The shape of the pressure-temperature curve and volume-temperature curve for the ideal gas is always a straight line.