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What is a chemical formula?

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A chemical formula is a way of expressing the composition of a substance using symbols for its constituent elements and numbers to indicate the quantity of each element.

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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 the element that are present in a molecule. For example, in H2O, the '2' indicates 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 chemical reaction. For example, in 2H2 + O2 -> 2H2O, the '2' before H2O means there are two water molecules produced.

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How do you determine the total number of atoms in a chemical formula?

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To find the total number of atoms, add the number of atoms of each element together, taking into account the subscripts.

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What is a balanced chemical equation?

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A balanced chemical equation has the same number of each type of atom on both sides of the equation, indicating that mass is conserved during the reaction.

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What is the difference between a reactant and a product in a chemical reaction?

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Reactants are the starting substances that undergo a chemical change, while products are the substances formed as a result of the reaction.

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What is the significance of the law of conservation of mass in chemical reactions?

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The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction, meaning the total mass of reactants equals the total mass of products.

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What does the term 'yield' mean in a chemical equation?

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The term 'yield' refers to the amount of product formed in a chemical reaction, often represented by an arrow in the equation.

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What is an example of a simple chemical reaction?

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An example of a simple chemical reaction is the combustion of methane: CH4 + 2O2 -> CO2 + 2H2O.

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What is a diatomic molecule?

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A diatomic molecule is a molecule composed of two atoms, which can be of the same or different elements, such as O2 (oxygen) or HCl (hydrogen chloride).