Question

The element potassium's atomic number is 19. Its relative atomic mass is 39.098. How many protons occur in a potassium atom?

Answer 1

Hint: Before solving this question, it is important to know the basic terms such as atomic number, relative atomic mass, electrons and protons.

Complete step by step answer:
- Electrons, protons and neutrons are the subatomic particles. Electrons are the subatomic particle which carries a negative charge, while protons are the subatomic particle with a positive charge and neutrons are the subatomic particle which has no charge. Protons and neutrons both are present in the nucleus of the atom whereas electrons revolve around the nucleus.
- Atomic number is the number of protons present in the nucleus of every atom of that element. Mass number is the sum of protons and neutrons present in the nucleus of the atom. Protons and neutrons are collectively known as nucleons.
Given in the question,
Atomic number of potassium = 19
Relative atomic mass = 39.089
Number of protons is equal to the atomic number of the element. Hence, the number of protons in potassium atom is = 19

Note: If we have to calculate the number of neutrons with the help of the given information, then the number of neutrons will be equal to the difference between the mass number of the atom and the atomic mass or the number of protons present in the atom. Mass number is the sum of protons and neutrons present in the nucleus of the atom. Protons and neutrons are collectively known as nucleons and they are present inside the nucleus of the atom.