Question

In the reaction, ${N_2} + 3{H_2} \to 2N{H_3}$, the ratio of volumes of nitrogen, hydrogen and ammonia is $1:3:2$. These figures illustrate the law of:
A. Constant proportions
B. Gay-Lussac
C. Multiple proportions
D. Reciprocal proportions

Answer 1

We can see that when nitrogen and hydrogen react with one other, volume contains a simple whole number ratio with each other. This must be given by any one of the gas laws.

Complete step by step answer:
We can state the law of constant proportion that a given chemical compound constantly comprises of its component elements in fixed ratio. It does not depend on its surface and method of preparation/synthesis.
We can state Gay Lussac’s Law of combining volumes that when gases react with each other, they do so in volumes that bear a simple ratio to one another, and to the volume of the gaseous products formed, at same temperature and pressure.
We can state the law of multiple proportions when the same two elements forms more than one compound, the different weights of one element which combine with the same weight of the other element are in the ratio of simple small whole numbers.
We can state the law of reciprocal proportion if two different elements react separately with a constant mass of a third element, the ratio of the weights in which they do so are either the same as or a simple multiple of the ratio of the weights in which they combine with each other.
In the reaction, ${N_2} + 3{H_2} \to 2N{H_3}$, the ratio of volume of Nitrogen, Hydrogen and ammonia is $1:3:2$. This is explained by Gay Lussac’s Law of combining volumes (or) Law of gaseous volumes.

So, the correct answer is Option B .

Note:
Some other gaseous laws are,
Boyle’s Law:
At constant temperature, the pressure and the volume of the gas are inversely related to each other.
$PV = K$
Charles Law:
At constant pressure, the temperature and the volume of the gas are proportionally related to each other.
$\dfrac{V}{T} = K$
Avogadro’s Law:
At constant pressure and temperature, the number of moles in the gas and the volume of the gas are proportionally related.
$\dfrac{V}{n} = K$
Where,
V represents the volume of the gas.
T represents the temperature of the gas in Kelvin.
K represents the constant.
P represents the pressure of the gas.
n represents the number of moles.