This sounds like a question about electron energy levels. The third principal energy level has three sublevels, s,p and d. The sublevels have various numbers of orbitals, which are regions of probability of finding an electron, and each orbital can have a maximum of two electrons.
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explain why heating a contained gas that is held at a constant volume increases its pressure. describe what happens to the volume of a balloon when it is taken outside on a cold winter day. the volume decreases. the molecules have less kinetic energy and cause less pressure on the inside of the balloon.