Compounds & Counting Atoms Review

Front

What is an element?

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means. Examples include hydrogen (H), oxygen (O), and carbon (C).

Front

Which of the following represents an element? H2O, H, NaCl, CaCO3

Back

H

Front

How many Sodium atoms are in 6NaCl?

Back

6

Front

What is a compound?

Back

A compound is a substance made up of two or more different elements that are chemically combined. Examples include water (H2O) and sodium chloride (NaCl).

Front

What cannot be broken down into other substances?

Back

Element

Front

Which of the following is NOT a compound? hydrogen, sodium chloride, water, carbon dioxide

Back

hydrogen

Front

What is a mixture?

Back

A mixture is a combination of two or more substances that are not chemically combined. Examples include air and salad.

Front

What is the chemical formula for water?

Back

H2O

Front

What does the subscript in a chemical formula indicate?

Back

The subscript indicates the number of atoms of the element in a molecule. For example, in H2O, the '2' indicates there are two hydrogen atoms.

Front

What is the difference between an element and a compound?

Back

An element is a single type of atom, while a compound is made up of two or more different types of atoms chemically bonded together.