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 is a coefficient in a chemical equation?

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A coefficient is a number placed in front of a compound or element in a chemical equation that indicates how many molecules or atoms are involved in the reaction.

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What are reactants in a chemical reaction?

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Reactants are the starting substances in a chemical reaction that undergo change to form products.

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In the reaction 2Mg + O2 -> 2MgO, what are the reactants?

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The reactants are magnesium (Mg) and oxygen (O2).

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If you have 200 grams of ice and 900 grams of water, what is the total mass after the ice melts?

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The total mass after the ice melts is 1,100 grams.

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

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To determine the number of atoms in a chemical formula, look at the subscripts next to each element. If there is no subscript, it means there is one atom of that element.

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In the formula 3H2O, what does the '3' represent?

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The '3' is the coefficient that indicates there are three molecules of water (H2O).

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What is a subscript in a chemical formula?

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A subscript is a small number written to the right of an element symbol that indicates the number of atoms of that element in a molecule.

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How many oxygen atoms are in the formula 2H2O?

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There are 2 oxygen atoms in the formula 2H2O.

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What happens to the mass of substances during a chemical reaction?

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The mass of substances remains constant during a chemical reaction; it is conserved.