P.1Chemical Reactions Unit Pre-Test

Front

What is a chemical change?

Back

A change in matter that forms one or more new substances with new chemical properties.

Front

What is a physical change?

Back

A change that does not alter the chemical composition of a substance.

Front

What are signs of a chemical change?

Back

Signs include color change, temperature change, gas production, and formation of a precipitate.

Front

What happens when baking soda and vinegar are mixed?

Back

They react to produce a new substance, carbon dioxide gas, which causes fizzing.

Front

What is the melting point of a substance?

Back

The temperature at which a solid becomes a liquid.

Front

What is a substance?

Back

A form of matter that has a definite composition and distinct properties.

Front

What is the difference between an element and a compound?

Back

An element is a pure substance made of only one type of atom, while a compound is made of two or more different types of atoms chemically bonded together.

Front

What is the formula for water?

Back

H₂O, which consists of two hydrogen atoms and one oxygen atom.

Front

What is an example of a physical change?

Back

Melting ice into water.

Front

What is an example of a chemical change?

Back

Burning wood, which produces ash and smoke.