IPA: //ˌfoʊtəʊˈkɛmɪkli//
KK: /fōtōˈkemɪk(ə)lē/
In a way that relates to the chemical reactions caused by light.
The plants grow photochemically, using sunlight to convert carbon dioxide into oxygen.
Photochemically → It is formed from "photo-" (from Greek "phōs", meaning light) and "chemical" (from Greek "khēmeia", meaning the art of transmuting metals). The word "photochemically" refers to processes that involve chemical reactions triggered by light.
Think of 'light' ('photo-') causing 'chemical' reactions — that's what photochemically means.