8th Grade Chemistry Review

Front

What does the principle of conservation of mass mean in chemical reactions?

Back

Matter is not created or destroyed.

Front

How many atoms of carbon (C) are in C6H12O6?

Back

6

Front

What is the rate of reaction?

Back

How fast a reaction is.

Front

What do the red numbers in a chemical equation represent?

Back

Coefficients.

Front

How many atoms of Oxygen are in 3Fe2O3?

Back

9

Front

What is a chemical reaction?

Back

A process where substances (reactants) are transformed into new substances (products).

Front

What is a reactant?

Back

A substance that undergoes change in a chemical reaction.

Front

What is a product in a chemical reaction?

Back

A substance that is formed as a result of a chemical reaction.

Front

What is the difference between a coefficient and a subscript in a chemical formula?

Back

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

Front

What is the law of definite proportions?

Back

A chemical compound contains the same elements in exactly the same proportions by mass, regardless of the size or source of the sample.