7.2 Review

Front

What is a physical change?

Back

A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition. Examples include getting a haircut, melting ice, or dissolving sugar in water.

Front

What are products in a chemical reaction?

Back

Products are the substances that are formed as a result of a chemical reaction. They appear on the right side of a chemical equation.

Front

What type of reaction is fireworks?

Back

Fireworks are an EXOthermic reaction, meaning they release energy in the form of heat and light.

Front

What is a chemical change?

Back

A chemical change is a change that results in the formation of new chemical substances. Examples include rusting iron, burning wood, or souring milk.

Front

Where are reactants found in a chemical equation?

Back

Reactants are the starting substances in a chemical reaction and are found on the left side of a chemical equation.

Front

What does it mean if a reaction is endothermic?

Back

An endothermic reaction is a chemical reaction that absorbs energy from its surroundings, usually in the form of heat.

Front

What is the difference between a physical change and a chemical change?

Back

A physical change affects the form of a substance but not its chemical composition, while a chemical change results in the formation of new substances.

Front

What is an example of a physical change?

Back

An example of a physical change is melting ice or getting a haircut.

Front

What is the role of coefficients in a chemical equation?

Back

Coefficients are numbers placed in front of the compounds in a chemical equation to indicate the number of molecules or moles of each substance involved in the reaction.

Front

What is the significance of subscripts in a chemical formula?

Back

Subscripts indicate the number of atoms of each element in a molecule. For example, in H2O, the '2' indicates there are two hydrogen atoms.