7th Mid-term SG #1

Front

What is the water cycle?

Back

The continuous movement of water above and below the surface of the Earth.

Front

Can molecules ever stop moving?

Back

Molecules can stop moving once the temperature has reached the coldest temperature possible.

Front

What type of change occurs when wood burns?

Back

A chemical change occurs because the atoms in the wood react with oxygen and rearrange to form new combinations of atoms and molecules.

Front

In an ice chest, which way does thermal energy move?

Back

From the soft drink to the ice cubes.

Front

What happens to heat when soda cans are placed in a cooler?

Back

The heat is leaving the soda and going into the ice.

Front

Define thermal energy.

Back

Thermal energy is the energy that comes from the temperature of matter.

Front

What is a chemical change?

Back

A process where substances combine or break apart to form new substances.

Front

What is a physical change?

Back

A change that affects one or more physical properties of a substance without altering its chemical composition.

Front

Explain the term 'molecule'.

Back

A molecule is a group of two or more atoms bonded together.

Front

What is the role of oxygen in combustion?

Back

Oxygen reacts with a fuel (like wood) to produce heat, light, and new substances.