Question

Helium atom has an atomic mass of 4 u and 2 proton in its nucleus. How many neutrons does it have?

Answer 1

Atomic mass = 4
No. of protons = 2
No. of neutrons = Atomic mass - No.of protons
= 4-2
= 2

Answer 2

The helium atom has 2 neutrons.

Explanation:

• The total moss of any given atom is provided to us by the addition of the masses of the protons and the neutrons which are present in the nucleus.

• Therefore we can write that Mass of atom = Proton + Neutron.

• The atomic mass of helium is given to us as 4u and it has a total of 2 protons.

• The atomic mass contributed by the two protons is 2u.

• Therefore the 4u is equivalent to 2u plus the neutrons.

• Therefore the entire number of the neutrons is given by subtracting 4 from 2 which gives us 2. Therefore 2 is the whole number of neutrons.

• No. of neutrons = Atomic mass - No.of protons

          = 4-2

           = 2

Learn more about helium

In the first period hydrogen and helium are not placed adjacent to each other why?

https://brainly.in/question/1217594

Helium gas consists of single atom.what mass of helium contains 6.022×10^23 atoms?

https://brainly.in/question/1600522