7th Grade Semester Exam

Front

What is a chemical property?

Back

A characteristic of a substance that can only be observed during a chemical reaction, such as reactivity with acid.

Front

What is a physical property?

Back

A characteristic of a substance that can be observed without changing its chemical composition, such as color or melting point.

Front

What does it mean for a planet to be in the habitable zone?

Back

It means the planet is at a distance from its star where conditions may be suitable for liquid water to exist.

Front

Can a planet in the habitable zone guarantee the presence of life?

Back

No, being in the habitable zone does not mean that life exists; it only indicates potential conditions for life.

Front

What determines the location of the habitable zone around a star?

Back

The size and temperature of the star determine where the habitable zone is located.

Front

What is a compound?

Back

A substance formed when two or more elements are chemically bonded together, which can only be separated by chemical means.

Front

What is a mixture?

Back

A combination of two or more substances that are not chemically bonded and can be separated by physical means.

Front

What is an element?

Back

A pure substance that cannot be broken down into simpler substances by chemical means.

Front

What is a chemical change?

Back

A change that results in the formation of new chemical substances, such as burning wood.

Front

What is a physical change?

Back

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