Question

why the atomic weight comes out to be fractional although proton and neutron cannot be divided​

Answer 1

Explanation:

Why is a neutron heavier than a proton?

4 Answers. The neutron is made of two down quarks and an up quark; the proton of two up quarks and a down quark. ... So, it's mostly the fact that the down quark is heavier than the up quark that makes the neutron heavier than the proton.