What elements are exceptions to the octet rule

The compound methyl butanoate smells like apples. its percent composition is 58.8% c, 9.9% h, and 31.4% o. what’s the empirical formula ?

Monkeys and bats have similar bone structure in their forelimbs. however, monkeys have longer forelimbs to use for climbing and swinging in trees. bats have shorter forelimbs to use for flight. which term best describes how monkey and bat forelimbs are related to each other? a. homologous b. embryonic c. analogous d. vestigial

Which type of orbits are found in the principal energy level n = 2 a - s b - s, f c - s, d d - s, p e - s, p, d