Which of the following statements is true about the structure of an atom? 1. The proton and neutron are of equal mass.
2. The electron is the most massive subatomic particle.
3. The electron cloud contains more mass than the nucleus.
4. The nucleus of an atom contains more mass than the electron cloud.
A
1 and 4
O
2,3, and 4
O
1 only
2 and 3