unit 2 KA8 - skin care Flashcards
what is ultraviolet (UV) radiation
UV radiation is a high-energy form of light, present in sunlight
what can exposure to UV light result in
molecules gaining sufficient energy for bonds to be broken, which is a process that is responsible for sunburn and ageing of the skin
what can be used to prevent the exposure of the skin to UV light
suncream
what are formed when UV light breaks bonds
free radicals
what are free radicals
these are atoms or molecules which are highly reactive due to the presence of unpaired electrons
what are the three steps of free radical chain reactions
- initiation
- propagation
- termination
how can equations involving free radicals be recognised
they can be recognised as representing an initiation, propagation or termination step
what are free radical scavengers
these are molecules that react with free radicals to form stable molecules and prevent chain reactions from occuring.
what are free radical scavengers added to
cosmetics, food products and plastics
