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Question
State what is a balanced equation with a relevant example. Give a reason why an equation is balanced with reference to the law of conservation of matter.
Solution
A balanced equation: “An equation is said to be balanced if the number of atoms of each element of the reactant is equal to the number of atoms of each element of the product.”
Example:
\[\ce{2Mg + O2->2MgO}\]
[Reactants] [Product]
Reactans has 2 atoms of Mg and 2 atoms of oxygen.
Products have 2 atoms of magnesium and 2 atoms of oxygen.
∴ Number of atoms of each element of reactants = Number of atoms of each element of the product.
- Reason for balancing equation: Law of conservation of matter says that “Matter is neither created nor destroyed during a chemical reaction.” This is possible only if the number of atoms of each element on both sides are equal i.e. in reactants and also in products. Hence a reaction is balanced.
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