Question

which of the element has same atomic no. as well as mass number
hydrogen
helium
oxygen
carbon

Answer 1

Atomic; Num... Symbol Name Atomic Mass...

1 H Hydrogen 1.00797

2 He Helium 4.00260

3 Li Lithium 6.941

Answer 2

Answer:

Hydrogen

Explanation:

Hydrogen atom has one electron and one proton . It doesn't have any nuetron in its nucleus. It only has one proton in its nucleus.

Atomic number is the no. of protons and neutrons in an atom and mass number is the no. of protons only.

So atomic no. of hydrogen = 1 proton + 0 neutron = only 1 unit.

Mass no. of hydrogen = 1 proton = 1 units

Hence atomic no. = mass no.

Hope that helps you☺️