Law of conservation of mass

Front

What is the Law of Conservation of Mass?

Back

The Law of Conservation of Mass states that mass cannot be created or destroyed in a chemical reaction; it can only change forms.

Front

If 200 grams of ice melts in 900 grams of water, what is the total mass of the water after the ice has melted?

Back

1,100 grams.

Front

What are reactants in a chemical reaction?

Back

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

Front

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

Back

Mg and O.

Front

What does the number below an element in a chemical formula represent?

Back

A subscript, which indicates the number of atoms of that element in a molecule.

Front

What is a molecule?

Back

A molecule is a group of atoms bonded together.

Front

What happens to matter in a chemical reaction according to the Law of Conservation of Mass?

Back

Matter cannot be created or destroyed; it can only be transformed or changed.

Front

What is a coefficient in a chemical equation?

Back

A coefficient is a number placed in front of a chemical formula to indicate how many molecules are involved in the reaction.

Front

What is the difference between a subscript and a coefficient?

Back

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

Front

Can matter be destroyed in a chemical reaction?

Back

No, matter cannot be destroyed; it can only change forms.