Review Chemistry Unit 4

Front

What is a physical change?

Back

A physical change happens when the substance does not change into a new substance with new chemical properties.

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, oxygen, and gold.

Front

What is the lightest element on the periodic table?

Back

Hydrogen is the lightest element on the periodic table.

Front

How many oxygen atoms are in the formula 2Na + 2H2O?

Back

There are 2 oxygen atoms in the formula 2Na + 2H2O.

Front

How many oxygen atoms are in the chemical formula C6H12O6?

Back

There are 6 oxygen atoms in the chemical formula C6H12O6.

Front

What is a chemical change?

Back

A chemical change occurs when a substance changes into a new substance with new chemical properties.

Front

What is the periodic table?

Back

The periodic table is a tabular arrangement of chemical elements, organized by their atomic number, electron configuration, and recurring chemical properties.

Front

What is a compound?

Back

A compound is a substance formed when two or more elements are chemically bonded together. Examples include water (H2O) and carbon dioxide (CO2).

Front

What is the difference between an element and a compound?

Back

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

Front

What is the chemical formula for water?

Back

The chemical formula for water is H2O.