List three ways in which the octet rule can sometimes fail to be obeyed

How many electrons does silver have to give up in order to achieve a sido noble gas electron configuration?

What is the ph of a 0.0010 m hno3? 1.0 3.0 4.0 5.0

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?