7th grade Science REVIEW 1st Semester

Front

What is a chemical change?

Back

A chemical change is a process where substances combine or break apart to form new substances with different properties. Example: Burning a candle.

Front

What is an example of a physical change?

Back

An example of a physical change is boiling water, where the water changes from liquid to gas but remains H2O.

Front

What are molecules made of?

Back

Molecules are made up of two or more atoms bonded together.

Front

What are the three methods of thermal energy transfer?

Back

The three methods of thermal energy transfer are conduction, convection, and radiation.

Front

What evidence supports the law of conservation of mass in a chemical reaction?

Back

The mass of the reactants before a chemical reaction is equal to the mass of the products after the reaction.

Front

What is the difference between an atom and a molecule?

Back

An atom is the smallest unit of an element, while a molecule is a group of two or more atoms bonded together.

Front

What happens to the atoms in a chemical reaction?

Back

Atoms are rearranged to form new substances, but the total number of atoms remains the same.

Front

What is an example of a gas produced in a chemical reaction?

Back

An example of a gas produced in a chemical reaction is carbon dioxide, which can be produced when vinegar reacts with baking soda.

Front

What is conduction?

Back

Conduction is the transfer of thermal energy through direct contact between materials.

Front

What is convection?

Back

Convection is the transfer of thermal energy through the movement of fluids (liquids or gases).