Question

why are there no neutrons in hydrogen

Answer 1

Stable atom nuclei have neutrons and protons at specific ratios. If you look at it from a "distance" you can imagine that when you put a bunch of protons together you create a lot of repulsive force, and in fact this can overcome the attractive force that works between them at very short distance .Adding some neutrons adds some nuclear attractive force without adding more repulsion

Answer 2

Answer:

Hydrogen can have no neutrons because it only has one proton. Many atoms need neutrons to remain stable because neutrons “space out" the protons. If the protons get too close, the repulsion between protons will be so big that the nucleus will break apart. In the case of hydrogen, there is only one proton.