Subatomic Particles

Front

What is an atomic number?

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 does an element with an atomic number of 9 have?

Back

9 protons.

Front

What is the relationship between atomic number and electrons in a neutral atom?

Back

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

Front

How many electrons does an element with an atomic number of 9 have?

Back

9 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

How many neutrons does an element with an atomic number of 9 and a mass of 19 amu have?

Back

10 neutrons.

Front

What is mass number?

Back

The mass number is the total number of protons and neutrons in an atom's nucleus.

Front

What is the mass number of Potassium (K) with 20 neutrons and an atomic number of 19?

Back

39 (19 protons + 20 neutrons).

Front

How many neutrons does a Hydrogen atom have?

Back

0 neutrons.

Front

What is the formula to calculate the number of neutrons in an atom?

Back

Number of Neutrons = Mass Number - Atomic Number.