Subatomic Particles of atoms

Front

What is the atomic number of an element?

Back

The atomic number is the number of protons in the nucleus of an atom, which determines the element's identity.

Front

How many protons are in a neutral atom of an element?

Back

In a neutral atom, the number of protons is equal to the number of electrons.

Front

What is the charge of a proton?

Back

A proton has a positive charge of +1.

Front

What is the charge of a neutron?

Back

A neutron has no charge, it is neutral.

Front

What is the charge of an electron?

Back

An electron has a negative charge of -1.

Front

How do you calculate the mass number of an atom?

Back

The mass number is calculated by adding the number of protons and neutrons in the nucleus.

Front

What is an isotope?

Back

An isotope is a variant of an element that has the same number of protons but a different number of neutrons.

Front

What subatomic particle determines the chemical properties of an element?

Back

The chemical properties of an element are primarily determined by the number of protons (and electrons).

Front

What is the role of neutrons in the nucleus of an atom?

Back

Neutrons help to stabilize the nucleus by offsetting the repulsive forces between protons.

Front

How many neutrons are in phosphorus-31?

Back

Phosphorus-31 has 16 neutrons (31 mass number - 15 protons = 16 neutrons).