Question

Assertion(A): Stoichiometric coefficient are the numbers which are put before compounds
or elements to balance the chemical equations. Reason: (R): Chemical equation is balanced to justify the law of conservation of mass.

Answer 1

Answer:

(a) Both Assertion and Reason are correct and reason is the correct explanation of Assertion.

Explanation:

Consider a chemical reaction.

N₂ + H₂ ➝ NH₃

When we balance the equation,

N₂ + 3H₂ ➝ 2NH₃

Here the stoichiometry coefficients are:

• Nitrogen - 1
• Hydrogen - 3
• Ammonia - 2

So, stoichiometry coefficients are the numbers which are put behind the elements or compounds and are required for balancing the chemical reaction.

Finding the Gram Molecular mass:

2(14) + 3(2) = 2(14 + 3(1))

⇒ 28 + 6 = 2(14 + 3)

⇒ 34 = 2(17)

⇒ 34 = 34

From the above observation, we can say that balancing of chemical reactions is done to justify the law of conservation of mass.

Answer 2

Answer: <A> both are correct and reason is the correct explanation of assertion