Law of Conservation of Mass

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What is the Law of Conservation of Mass?

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The Law of Conservation of Mass states that mass is neither created nor destroyed in a chemical reaction. The total mass of the reactants equals the total mass of the products.

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What does a subscript in a chemical formula indicate?

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A subscript indicates the number of atoms of an element in a molecule. For example, in H2O, the '2' is a subscript indicating there are 2 hydrogen atoms.

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What does a coefficient in a chemical equation represent?

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A coefficient indicates the number of molecules or moles of a substance. For example, in 4NH3, the '4' is a coefficient indicating there are 4 molecules of ammonia.

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How do you determine the number of atoms in a compound?

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To determine the number of atoms in a compound, multiply the coefficient by the subscript for each element. For example, in 4NH3, there are 4 nitrogen atoms and 12 hydrogen atoms.

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What is the difference between a subscript and a coefficient?

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A subscript indicates the number of atoms of an element in a molecule, while a coefficient indicates the number of molecules of a compound.

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How many total atoms are in the compound 4NH3?

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There are 16 total atoms in 4NH3 (4 nitrogen + 12 hydrogen).

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What is the purpose of balancing a chemical equation?

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The purpose of balancing a chemical equation is to ensure that the number of atoms of each element is the same on both sides of the equation, in accordance with the Law of Conservation of Mass.

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Can you change subscripts to balance a chemical equation?

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No, you cannot change subscripts to balance a chemical equation. You can only change coefficients.

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What happens if a chemical equation is not balanced?

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If a chemical equation is not balanced, it violates the Law of Conservation of Mass, meaning the mass of reactants does not equal the mass of products.

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What is an example of a balanced chemical equation?

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An example of a balanced chemical equation is 2H2 + O2 → 2H2O, where the number of each type of atom is the same on both sides.