revision unit 12 Flashcards
describe the kinetic theory of matter
solid: the particles of solid are held next to each other in fixed positions, they vibrate in there fixed positions, so the solids keep its own shape, and they have a fixed volume and a higher density than gas.
liquid: the particles in liquids are in contact with each other. they move at random. so liquid doesn’t have a shape but it flows they have a fixed volume, and a higher density than gas
gas: the particles in a gas move about at random much faster than liquid and gas, they are much further apart than the particles of liquids and gases, so it has a less density than liquid or solid
the temperature of a heated substance depend on
the amount of energy supplied to it, and the mass of the substances , and what substance it is
what is specific heat capacity
it is the energy need or energy transferred to 1 kg of the substances to raise is temperature by 1c
E = m x c x change of temperature in degrees
what happens to a substance once it hits there boiling or melting points
when an object hits its boiling or melting point its temperature would stay constant.
what is latent heat
it is the energy supplied to a substance when it changes its state
what is specific latent heat of fusion
it is the energy needed to melt 1kj of a substance at is melting point without changing its temperature
what happens to a substance below its melting point once it is being heated
the temperature of the substance would keep increasing till it reaches its melting point. as the energy supplied to the object would increase the kinetic energy of particles
what happens to a substance which is at its melting point once it is being heated
it would melt and turn into a liquids, the temperature of the substances wont change until its melted by latent heat of fusion which is used to break particles free from each other
what happens to a substance below its boiling point point once it is being heated
the temperature of the substance would keep increasing till it reaches its boiling point. as the energy supplied to the object would increase the kinetic energy of particles.
what happens to a substance which is at its boiling point once it is being heated
it would boil and turn into a vapor, the temperature of the substances wont change until its boiled by latent heat of vaporization which is used to break particles free from each other
what is specific latent heat of vaporization
it is the energy needed to change one kg of a substance at its boiling point from a liquid to a vapor
