molecules and matter Flashcards
what is density
mass at a given volume, how packed something is w particles
density equation
mass
density x volume
how to find volume of water
measure mass of beaker before and after water is added and subtract
explain required practical 5 density
so you find the mass of an object like normal but if its an odd shape the volume is hard to determine. you get a eureka can of water with a spout, when you add the object water will be displaced through the spout and the volume of the displaced water is equal to the vol of the object
what happens to particles when state chnges
though their positions change they do not gain or lose any so they dont change mass
what is latent heat
energy needed to change 1kg of a substances state w no change in temp
what is the dif between boiling and evapourating
boiling is a fixed temp when bubbles are formed inside the liquid that rise to become a gas
evapouration happens only at the surface under the boiling point
what does fusion describe
melting when two dif solids are ‘fused’ together
whats internal energy
total kinetic and pot energy stored by particles in a system- their movement and their potential due to their relations to eachother NOT grav pot and the objects kinetic
what is the energy change in temo equation
e =
mass x c (heat capacity) x change in temp
whe a substance is heated…
internal energy increases as theres more kinetic between particles
how does pressure of a gas increase
they gain speed from heat and so hit the surface more rapidly and so speed the number of impacts per sec
what is latent heat of fusion
energy needed to melt/ boil 1kg of a subsatnce froma solid to a liquid w no temp change
latent heat equation
energy
mass x latent heat
what is latent heat of vapourisation
energy needed to change the state (by breaking bonds) of 1kg of substnace from liquid to a vapour with no temp change
