Protons are not the only subatomic particle that has a charge, electrons do to and they are negatively charged. Neutrons are situated in the nucleus of the atom, which means that they do not orbit it. Subatomic particles have different masses.
You are then left with Electrons are the subatomic particles with the smallest mass as your answer.
There are 150 neutrons in 15N
One atom of carbon weighs exactly 12/6.022x10^23 = 1.9927x10^-23 grams<span>.</span>
The answer is B. A good way determine this is how far right the element is on the periodic table. The further right the element is, the more electronegative it is meaning it is more willing to accept an electron. This can be explained using the valence electrons and how many need to be added or removed to complete the octet. The further right you are, the easier it is for the element to just gain a few electrons instead of loose a bunch. Noble gases are the exception to this since they don't normally react though.
This is so basic bro u gotta first move