Question

SO2 at STP contained in a flask was replaced by O2 under identical conditions of pressure temperature and volume then the weight of O2 will be dash of SO2

Answer 1

Answer: The weight of oxygen gas will be half that of weight of sulfur dioxide.

Explanation:

To calculate the number of moles, we use the equation given by ideal gas equation:

PV = nRT

Or,

$PV=\frac{w}{M}RT$

where,

P = Pressure of the gas

V = Volume of the gas

w = Weight of the gas

M = Molar mass of gas

R = Gas constant = $0.0820\text{ L atm }mol^{-1}K^{-1}$

T = Temperature of the gas

We know that:

Molar mass of sulfur dioxide = 64 g/mol

The equation becomes:

$PV=\frac{w_{SO_2}}{64}RT$     .....(1)

Molar mass of oxygen = 32 g/mol

The equation becomes:

$PV=\frac{w_{O_2}}{32}RT$     .....(2)

Dividing equation 2 by equation 1, we get:

$\frac{PV}{PV}=\frac{\frac{w_{O_2}}{32}RT}{\frac{w_{SO_2}}{64}RT}\\\\1=\frac{\frac{w_{O_2}}{32}}{\frac{w_{SO_2}}{64}}\\\\1=\frac{w_{O_2}}{32}\times \frac{64}{w_{SO_2}}\\\\w_{O_2}=\frac{w_{SO_2}}{2}$

Hence, the weight of oxygen gas will be half that of weight of sulfur dioxide.