Question

which isotope of hydrogen atom have same number of lectrons, protons and neutrons and how much is the number

Answer 1

It's is 1H2
Here protons=electrons=neutrons=1


Explaination :

Protons =electrons =1

Neutrons=2-1=1

Answer 2

contains has three isotopes, Protium, Deuterium, and Tritium. All these contain only one electron and one proton. The only difference is in their neutron number.

Protium contains one electron, one proton, and zero neutrons.

Deuterium contains one electron, one proton, and one neutron.

Tritium contains only one proton and electron, and two neutrons.

So Deuterium is the isotope which has an equal number of electrons, protons and neutrons.