Question

Dalton’s law of partial pressures is not applicable to which of the following mixture of gases?
This question has multiple correct options.
(a) ${{\text{H}} _ {2}} \text {+} {{\text{F}} _ {2}}$
(b) $\text{N}{{\text{H}} _ {3}} \text {+ HCl}$
(c) $\text{S}{{\text{O}} _ {2}} \text {+ C} {{\text{l}} _ {2}}$
(d) ${{\text{H}} _ {2}} \text {+} {{\text{O}} _ {2}}$

Answer 1

Dalton’s law is used there where the gaseous mixture consists of chemically non- reacting gases. Identify those gaseous mixtures from the above which do not undergo chemical reaction and then you can easily find the gaseous mixture which obeys Dalton's law.

Complete step by step answer:
First of all, we should know Dalton's law of partial pressure. This law states the total pressure of a mixture containing a larger number of gases is the sum of the partial pressures (it is that pressure of gas if it is allowed to occupy the whole volume of the reaction mixture) of each of the individual gas molecules. Example: consider a mixture of gases as gas 1, gas2 and gas 3 and let P is the individual pressure of each gas, then the total; pressure of the gas according to the Dalton’s law is;
Total pressure of the mixture = Pressure of gas 1 + Pressure of gas 2 + Pressure of gas
= P+P+P
=3P
The Dalton’s is only applicable to the mixture which consists of the non-reacting gases i.e. the gases do not react chemically and only in that case the sum total of the partial pressure of each gas is equal to the total pressure of the mixture and the Dalton’s law is not applicable where the reaction mixture consists of the reacting gases as in that case there will no individual partial pressure of the gas and hence Dalton’s won’t be applied in such cases.
In the above given ,all the gaseous mixture, the Dalton’s law is not applicable because these gaseous reaction mixtures i.e. ${{\text{H}}_{2}}\text{ + }{{\text{F}}_{2}}$ ,$\text{N}{{\text{H}}_{3}}\text{ + HCl}$,$\text{S}{{\text{O}}_{2}}\text{ + C}{{\text{l}}_{2}}$ and ${{\text{H}}_{2}}\text{ + }{{\text{O}}_{2}}$ chemically react with each other .
So, the correct answer is “OptionA,B, C and D”.

Note: The Real do not show ideal behaviour and only at the low pressure and high temperature, these gases behave as ideal gases, that means, the Dalton’s law of partial pressure is only applicable at low temperature and pressure and at high pressures and low temperatures, Dalton’s law is not applicable.