Atomic Number, Atomic Mass

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

What is atomic mass?

Back

Atomic mass is the weighted average mass of an element's isotopes, measured in atomic mass units (amu).

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 relationship between protons and electrons in a neutral atom?

Back

In a neutral atom, the number of protons equals the number of electrons.

Front

What is a neutron?

Back

A neutron is a subatomic particle found in the nucleus of an atom, with no electric charge.

Front

What is a proton?

Back

A proton is a positively charged subatomic particle found in the nucleus of an atom.

Front

What is the average atomic mass listed on the periodic table?

Back

The average atomic mass is the weighted average of the masses of an element's isotopes, reflecting their natural abundance.

Front

How many neutrons are in a carbon-12 atom?

Back

A carbon-12 atom has 6 neutrons.

Front

If an atom has 8 protons and 7 neutrons, what is its mass number?

Back

The mass number is 15 (8 protons + 7 neutrons).

Front

What is the significance of the atomic number in the periodic table?

Back

The atomic number determines the position of an element in the periodic table and its chemical properties.