Comparing Subatomic Masses Atoms are made up of subatomic particles including protons and electrons. The mass of a proton is about 1.6726 x
10-27 kg and the mass of an electron is about 9.1094 x 10-31 kg. Determine how much mass a proton and electron
has combined. Express the result in scientific notation.
O 1.6717 x 10-27
O 16,717 * 10-31
O 1.6735 x 10-27
O 16,735 x 10-31

An  atom  (ours, not carroll's) consists of a positively charged  nucleus, surrounded by one or more negatively charged particles called  electrons. the positive charges equal the negative charges, so the atom has no overall charge; it is electrically neutral. most of an atom's mass is in its nucleus; the mass of an electron is only 1/1836 the mass of the lightest nucleus, that of hydrogen. although the nucleus is heavy, it is quite small compared with the overall size of an atom. the radius of a typical atom is around 0.1 to 0.25 nanometres (nm), whereas the radius of a nucleus is about 10-6  nm.  *  if an atom were enlarged to the size of the earth, its nucleus would be only 200 feet in diameter and could easily rest inside a small football stadium.read more on -