7.1 chemical reactions

when a substance undergoes a chemical change and produces new substances that have different properties from the original substance

chemical reactions

A combination of symbols and subscript represent a chemical reaction

chemical equation

The original substances that undergo a chemical reaction (on the left side of the equation)

Reactant

The new substances produced by the chemical (on the right side of the equation)

product

The arrow in the equation

yield sign

Massive energy cannot be created or destroyed. It only changes into different forms.

Law of conservation of mass and energy

During a chemical reaction, the total mass of the reactants must ____ the total mass of the products

equal

in order to show that mass is conserved during a reaction, a chemical equation must be ____

balanced

why do we balance equations?

in order at the law of conservation of mass and energy is upheld (true)

A balanced chemical equation has the ___ number of atoms of each element on the left side of the equation (____) as it does on the right side of the equation (___)

same

reactants

products

tell the number of molecules; large number in front of the compound

Coefficient

Tell us the number of atoms; small number; do not change these

Subscript