Assertion: hypochlorite's chlorine | /r/AtLocation | water
Facets:
Source sentences:
text: When chlorine is added to water, there must be enough chlorine to satisfy the demand and also to leave a small amount of chlorine residual to kill the germs left in the water and help prevent re-contamination.
text: When disinfecting household drinking water the one per cent chlorine is added to the water and left for 20 minutes to allow sufficient contact time for the chlorine to work.
text: Rook’s discovery of THMs in drinking water led to research on other chemicals formed when chlorine is added to water, and to the health effects of these chemicals.