Atomic number, Mass number and Isotopes

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 the mass number of an element?

Back

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

Front

What are isotopes?

Back

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

Front

How do you calculate the number of neutrons in an atom?

Back

Number of neutrons = Mass number - Atomic number.

Front

What element has an atomic number of 22?

Back

Titanium.

Front

Which element has a mass number of 79?

Back

Selenium.

Front

What is the atomic number of potassium?

Back

The atomic number of potassium is 19.

Front

How many protons does cobalt have?

Back

Cobalt has 27 protons.

Front

If an element has 28 neutrons and an atomic number of 27, what is its mass number?

Back

The mass number is 55 (27 protons + 28 neutrons).

Front

What is the relationship between atomic number and mass number?

Back

The atomic number is the number of protons, while the mass number is the sum of protons and neutrons.