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 reactants equals the total mass of 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 two 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 involved in a reaction. For example, in 2H2 + O2 -> 2H2O, the '2' before H2O indicates there are two water molecules produced.

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How do you determine if a chemical equation is balanced?

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A chemical equation is balanced when the number of atoms of each element is the same on both sides of the equation.

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What is the importance of balancing chemical equations?

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Balancing chemical equations is important because it reflects the conservation of mass and ensures that the same amount of each element is present before and after a reaction.

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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, as this would change the identity of the substance.

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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 hydrogen and oxygen atoms is the same on both sides.

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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 does not accurately represent the reaction, violating the Law of Conservation of Mass.

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What is the role of coefficients in balancing equations?

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Coefficients are used to adjust the number of molecules of reactants and products to ensure that the equation is balanced.

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What is a reactant in a chemical reaction?

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A reactant is a substance that undergoes a change during a chemical reaction, found on the left side of a chemical equation.