Balance this chemical equation below: NaHCO3 = H2O + CO2 + Na2CO3
The Correct Answer and Explanation is:
Balanced Chemical Equation:
2NaHCO₃ → H₂O + CO₂ + Na₂CO₃
Explanation:
Balancing a chemical equation involves ensuring the same number of each type of atom appears on both sides of the equation. The given reaction is the thermal decomposition of sodium bicarbonate (baking soda), which breaks down when heated to form water, carbon dioxide, and sodium carbonate.
Step-by-step Process:
The unbalanced equation is:
NaHCO₃ → H₂O + CO₂ + Na₂CO₃
First, list the elements involved: Sodium (Na), Hydrogen (H), Carbon (C), and Oxygen (O).
Left Side:
- Na = 1
- H = 1
- C = 1
- O = 3
Right Side (before balancing):
- H₂O: H = 2, O = 1
- CO₂: C = 1, O = 2
- Na₂CO₃: Na = 2, C = 1, O = 3
To balance sodium (Na), place a coefficient of 2 before NaHCO₃:
2NaHCO₃ → H₂O + CO₂ + Na₂CO₃
Now, recount the atoms:
Left Side:
- Na = 2
- H = 2
- C = 2
- O = 6
Right Side:
- H₂O: H = 2, O = 1
- CO₂: C = 1, O = 2
- Na₂CO₃: Na = 2, C = 1, O = 3
Total on Right Side:
- Na = 2
- H = 2
- C = 2
- O = 1 + 2 + 3 = 6
All atoms now match on both sides, so the equation is balanced.
This reaction is an example of a decomposition reaction, commonly seen in baking processes. Heating sodium bicarbonate produces carbon dioxide gas, which helps dough or batter rise. The leftover solid sodium carbonate and water vapor are byproducts of the decomposition. Balancing ensures the reaction follows the law of conservation of mass, meaning matter cannot be created or destroyed, only rearranged.
