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Question
The chemical equations are balanced to satisfy one of the following laws in chemical reactions. This law is know as:
(a) law of conservation of momentum
(b) law of conservation of mass
(c) law of conservation of motion
(d) law of conservation of magnetism
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Solution
(b) law of conservation of mass
Equations are balanced when the mass of atoms of different elements in reactants' side equals the atoms in products' side. If it is not so, it means that matter is either created or destroyed in reactions, which is impossible.
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