Question

Given the element argon which has 20 protons and 20 neutrons.Find the atomic number, mass number, number of electrons and electronic configuration for the same.

Answer 1

• Atomic number is the number of protons in an atom.
• Since the number of protons is given as 20, the atomic number will be also 20.
• Also the number of electrons will be equal to the number of protons in a neutral atom. Thus the number of electrons=20.
• Electronic configuration, is the arrangement of electrons in energy levels around an atomic nucleus.
• Thus electronic configuration:2,8,8,2.
• Mass number is the sum of the number of protons and neutrons in an atom.
• Thus mass number=(20+20)=40.