Escential chemistry

No, my title isn't a spelling mistake. A surprising number of nouns in chemistry end in -escence, while the adjective ends -escent and the verb -esce. We mustn't confuse -escence with essence, although they sound the same - there is an essential difference.

The ending -escence means becoming or beginning to be from the Latin -escens, beginning to be. So, senescence means beginning to be old. This word ending is found in many technical words, and knowing what the ending means often helps you to guess the meaning. For example, Rubescent and rufescent both mean the same thing - becoming red, from two words for red. Likewise virescent and viridescent both mean becoming green. Acidescent and alkalescent are opposites, meaning becoming acid or alkaline respectively. Liquescent (and deliquescent) means becoming liquid (sometimes used to describe melting) but there seems to be no similar word for becoming solid. However, vitrescent means turning into glass.