Atoms, Elements, Molecules, Compounds

Front

What is an atom?

Back

The smallest unit of an element, consisting of protons, neutrons, and electrons.

Tags

NGSS.MS-PS1-1

Front

What is an element?

Back

A pure substance that cannot be broken down into simpler substances and is made up of only one kind of atom.

Front

What is a molecule?

Back

A group of two or more atoms bonded together, which can be of the same or different elements.

Tags

NGSS.MS-PS1-1

Front

What is a compound?

Back

A substance formed when two or more different elements are chemically bonded together.

Tags

NGSS.MS-PS1-1

Front

Is water (H2O) a molecule or a compound?

Back

Water is both a molecule and a compound.

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NGSS.MS-PS1-1

Front

What is the difference between a molecule and a compound?

Back

All compounds are molecules, but not all molecules are compounds. Molecules can consist of the same type of atoms.

Tags

NGSS.MS-PS1-1

Front

What is ammonia (NH3)?

Back

Ammonia is a compound made up of nitrogen and hydrogen atoms.

Tags

NGSS.MS-PS1-1

Front

What is the chemical formula for carbon dioxide?

Back

The chemical formula for carbon dioxide is CO2.

Tags

NGSS.MS-PS1-1

Front

Can an element exist as a molecule?

Back

Yes, some elements, like O2 (oxygen), exist as diatomic molecules.

Tags

NGSS.MS-PS1-1

Front

What is a homogeneous mixture?

Back

A mixture that has a uniform composition throughout, such as saltwater.