Atomic Number and Atomic Mass

Front

What is the mass number defined as?

Back

The mass number is defined as the number of protons and neutrons in an atom.

Front

Which particle has a positive charge?

Back

The proton has a positive charge.

Front

What is the atomic number of an atom?

Back

The atomic number is the number of protons in the nucleus of an atom.

Front

Which subatomic particle has a negative charge?

Back

The electron has a negative charge.

Front

What is the relationship between atomic number and element identity?

Back

The atomic number determines the identity of an element; each element has a unique atomic number.

Front

What is the atomic mass unit (amu)?

Back

The atomic mass unit (amu) is a standard unit of mass that quantifies mass on an atomic or molecular scale.

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 the charge of a neutron?

Back

A neutron has no charge; it is neutral.

Front

What is the significance of isotopes?

Back

Isotopes are variants of the same element that have the same number of protons but different numbers of neutrons.

Front

How does the number of electrons relate to atomic charge?

Back

The number of electrons determines the overall charge of an atom; if there are more electrons than protons, the atom is negatively charged.