Types Of Matter Flashcards
what does the strength of intermolecular forces depend on
temperature
pressure
the material ( type of bond and structure)
why do solids expand slightly when heated
the particles vibrate more
why do liquids expand slightly when heated
the particles move faster
what is the motion of gas particles as they move
travel in straight lines until they collide
explain 3 limitations of particle theory
particles are not solid, inelastic or spheres like the model shows
model doesn’t show forces between particles
size of particles and distance between them are not shown
what is a bulk property
properties that stay the same regardless on the amount of atoms are in the sample for example density and melting point.
they depend on the interaction of particles so a single atom would behave differently
explain melting
particles gain energy so vibrate more which weakens intermolecular forces. when temperature reaches melting point the particles have enough energy to break free from their positions
explain boiling
heated and particles gain more energy so they more faster which weakens attractive forces. at boiling point the particles have enough energy to overcome the forces between hem
explain freezing
liquid cools, particles have less energy so move around less so not enough energy to overcome attraction between particles so particles are less free to move
what is one micrometre in meters
1 x 10^-6
what is one nanometre in meters
1 x 10^-9
how big are coarse particles
2500nm - 10000nm
how big are fine particles
100nm - 2500nm
how big are nanoparticles
1nm - 100nm
what is the diameter of a typical atom
0.1nm
why are nanoparticles worthy of having a branch of science devoted to them
they have different properties to the material in bulk
what are 6 uses of nanoparticles
catalysts - platinum is used in fuel cells
medicine - easily absorbed by the body so can deliver drugs
electronics - eg making tiny memory chips
deodorants - silver nanoparticles are added because they have antibacterial properties
sun cream - give better skin coverage and better at protecting skin from uv
cosmetics - deliver active ingredients to lower layers of skin in anti aging creams
disadvantages of nanoparticles
we don’t know long term impacts on health
may cause environmental damage
