Language of Chemistry Test - 1

The balanced and molecular form of the given equation is written as:

   S (s)  +  2H₂SO₄ (aq)  →  3SO₂ (g)  +   2H₂O (l)
Sulphur  Sulphuric acid   Sulphur dioxide  Water

The electrons that take part in a chemical reaction are called valence electrons.

A chemical equation is said to be balanced when the number of atoms of each element involved in the reaction is equal on both the sides of the reaction. In the chemical equation given in the alternative D, both reactant side and product side contain one carbon atom, two sulphur atoms, and eight oxygen atoms. Hence, this chemical equation is balanced.

      CS₂ (s)     +     4O₂ (g)   →   CO₂ (g)   +    2SO₂ (g)
Carbon disulphide  Oxygen  Carbon dioxide  Sulphur dioxide  

Hence, the correct answer is option D.

Why alternative A is wrong:

There are two atoms of carbon on the reactant side, whereas there is only one atom of carbon on the product side. Hence, the chemical equation is not balanced.

Why alternative B is wrong:

There is only one atom of sulphur on the reactant side, whereas there are two atoms of sulphur on the product side. Hence, the chemical equation is not balanced.

Why alternative C is wrong:

There are 15 atoms of oxygen on the reactant side, whereas there are only eight atoms of oxygen on the product side. Hence, the chemical equation is not balanced.

The balanced chemical equation for the reaction between carbon and oxygen is represented as

 C (s)  +  O₂ (g)  →  CO₂ (g)
Carbon  Oxygen  Carbon dioxide
1 mole    1 mole        1 mole

One mole of carbon combines with one mole of oxygen to form one mole of carbon dioxide.

Rate of the reaction is not conveyed by the balanced chemical equation.
 

Carbon has electronic configuration 2, 4. It can achieve neon gas configuration−− i.e., 2, 8 by sharing of four electrons.