Atoms Elements Compounds 7th Grade Test Review

Front

What is an atom?

Back

An atom is the smallest unit of matter that retains the properties of an element.

Front

What is an element?

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means.

Front

What is a compound?

Back

A compound is a substance formed when two or more elements chemically bond together in fixed proportions.

Front

How many atoms are in a molecule of Al₂O₃?

Back

There are 5 atoms in a molecule of Al₂O₃ (2 Aluminum and 3 Oxygen).

Front

How many Nitrogen atoms are in (NH₄)₂CrO₄?

Back

There are 2 Nitrogen atoms in (NH₄)₂CrO₄.

Front

What is a mixture?

Back

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

Front

What is the chemical formula for Calcium Carbonate?

Back

The chemical formula for Calcium Carbonate is CaCO₃.

Front

What is the difference between an element and a compound?

Back

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

Front

What does the subscript in a chemical formula indicate?

Back

The subscript in a chemical formula indicates the number of atoms of the element present in the molecule.

Front

What is the significance of the periodic table in chemistry?

Back

The periodic table organizes elements based on their atomic number and properties, providing a useful reference for understanding chemical behavior.