A ___ change does not produce new substances.

___ are the starting substances in a chemical reaction.

Atoms rearrange when chemical ___ between atoms break.

When chemical formulas differ, they represent different ___.

A chemical formula contains ___ and ___ to describe the makeup of a compound.

A ___ is a number placed in front of an element symbol or a chemical formula in an equation.

A change in energy is another sign that a ___ has occurred.

The starting substances and the substances produced have different physical and chemical ___.

During a ___ change, new substances form.

To show that mass is conserved, a chemical equation must show that the number of each type of atom must be ___, or the same on both sides of the equation.

Two or more reactants are separated by ___ signs, as are any two or more products.

Sometimes, changes in ___ properties, such as color or odor, indicate a chemical reaction.