Full Idea
Examples where reductionism seems to give a good account of things are light, genes, temperature and transparency.
Gist of Idea
Reductionism is good on light, genes, temperature and transparency
Source
report of Jaegwon Kim (Mind in a Physical World [1998], §1 p.025) by PG - Db (ideas)
Book Reference
Kim,Jaegwon: 'Mind in the Physical World' [MIT 2000], p.25
A Reaction
This a fairly simple examples, thoroughly confirmed by science a long time ago. Life is a nicer example, because it is more complex and less obvious, but pretty much beyond dispute these days.