Chem Midterm Review

Front

What is a pure substance that cannot be broken down into another substance?

Back

Element (examples: H, O, C)

Front

What type of properties include color, shape, and size?

Back

Physical properties

Front

What two types of measurements make up density?

Back

Mass and Volume

Front

What is the chemical symbol for Helium?

Back

He

Front

What did Mendeleev do by leaving a gap in his periodic table?

Back

To account for unknown elements and their associated properties.

Front

What is the definition of an atom?

Back

The smallest unit of an element that retains the properties of that element.

Front

What is a molecule?

Back

A group of two or more atoms bonded together.

Front

What is a compound?

Back

A substance formed when two or more elements chemically bond together.

Front

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

Back

A chemical change results in the formation of new substances, while a physical change does not.

Front

What is the law of conservation of mass?

Back

Mass is neither created nor destroyed in a chemical reaction.