Answer:
Electron → Negative Charge → Outside Nucleus → Less than 1 amu
Proton → Positive Charge → Inside Nucleus → 1 amu
Neutron → No charge → Inside Nucleus → 1 amu
The atomic mass of helium is the bottom number underneath its symbol. The atomic mass is 4.0026. Since helium only have 2 protons, then helium has 2 neutrons because you subtract the atomic number from the atomic mass to find the neutron count. The atomic number is the top number above "He". The atomic number of helium is 2 and it refers to the amount of protons.
