Write the balanced equation for the following chemical reactions.

(iii) Sodium + Water → Sodium hydroxide + Hydrogen

 

Answer

(iii) Sodium + Water → Sodium hydroxide + Hydrogen

The skeletal chemical equation of the above reaction is

 

Na + H 2 O  →  NaOH + H 2

 

Name of the element

No. of atoms in Reactants

No. of atoms in Product

Sodium

1

1

Hydrogen

2

3

Oxygen

1

1

 

  1. Number of atoms of Hydrogen in reactants number of atoms of Hydrogen in products
    To balance number of Hydrogen,
    We multiply the NaOH in the product by 2 (If H2 is multiplied, the total number of H in the product will be odd while that in the reactant is even. This will make balancing difficult.)
    The chemical equation becomes

    Na + H 2 O  →  2 NaOH + H 2

 

Name of the element

No. of atoms in Reactants

No. of atoms in Product

Sodium

1

2

Hydrogen

2

4

Oxygen

1

2

 

  1. Now ,
    Number of atoms of Sodium in reactants number of atoms of Sodium in products
    To balance number of Sodium,
    We multiply the Na in the Reactants by 2
    The chemical equation becomes

    2 Na + H 2 O  →  2 NaOH + H 2

 

Name of the element

No. of atoms in reactants

No. of atoms in products

Sodium

2

2

Hydrogen

2

4

Oxygen

1

2



  1. Now,
    Number of atoms of Hydrogen in reactants number of atoms of Hydrogen in products
    To balance Hydrogen and Oxygen,
    We multiply H 2 O in the Reactants by 2

    2 Na + 2 H 2 O  →  2 NaOH + H 2

 

Name of the element

No. of atoms in reactants

No. of atoms in products

Sodium

2

2

Hydrogen

4

4

Oxygen

2

2

 

Now, all the elements are balanced and the balanced equation is

2 Na + 2 H 2 O  →  2 NaOH + H 2

 

2 Na + 2 H 2 O  →  2 NaOH + H 2

 

  1. Class 10
  2. Chapter 1 Class 10 - Chemical Reactions and Equations (Term 1)

About the Author

CA Maninder Singh's photo - Founder at Teachoo
CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo