Changes

[[NanoparticleNanoparticles]]s are small clumps of [[atom]]s which are between 1 and 100 [[nanometre]]s ([[billion]]ths of a [[metre]]) in [[length]], [[width]] or [[height]].

: A [[Hydrogen]] [[atom]] has a [[radius]] of 0.1[[nanometre]]s so 10 [[Hydrogen]] [[atom]]s lined up can make one [[nanometre]]. A [['''nanoparticle]] ''' may have a [[width]] of as little as 10 [[atom]]s or as many as 1000 [[atom]]s. (NB [[Hydrogen]] is being used as a comparison for the [[width]] and most [[nanoparticlenanoparticles]]s are made of other types of [[atom]].): A [[substance]] that is broken down into [[nanoparticlenanoparticles]]s may have very different [[property|properties]] to large amounts of the [[substance]].: The [[Surface Area to Volume Ratio|surface area to volume ratio]] of [[nanoparticlenanoparticles]]s is much higher than large [[Volume (Space)|volumes]] of the same [[substance]]. It is this large [[Surface Area|surface area]] compared to the [[Volume (Space)|volume]] that gives it the different [[property|properties]].: In 'bulk' [[material]]s a very small proportion of [[atom]]s exist on the surface of the [[material]]. However, for [[nanoparticlenanoparticles]]s a much larger proportion of [[atom]]s exist on the surface allowing those [[particle]]s to interact with others around it.