2: States of Matter and Mixtures

chlorination

a process used in water treatment where chlorine gas is injected into the water to kill any microbes

chromatography

a process used to separate substances in a mixture. separation of the substance depends on distribution between a mobile phase and a stationary phase

crystallisation

a separation technique that involves heating a solution until crystals start to form, leaving the solution to cool and then filtering the formed crystals from the solution

filtration

a separation technique used to separate an insoluble solid from a solution

fractional distillation

a process where a mixture is heated and the liquids that have different boiling points become gasses at different point, and so can be separated

gas

the state of matter where the particles have the most energy

ground water

water which collects in rocks that then trap the water underground

liquid

the state of matter where the particles are arranged randomly and close together

melting point data

data which can be used to evaluate the purity of a substance

Sharp melting point

where a pure substance has very little variation in melting point data

mixture

contains at least 2 different elements or compounds which are not chemically bonded together

mobile phase

the fluid which moves through the chromatography system, carrying the mixture which is to be separated

paper chromatography

a type of chromatography which used paper as the stationary phase and a solvent as the mobile phase. The distance that the substance makes it up the paper depends on it’s solubility

particle theory

the theory which models the 3 states of matter by representing the particles as small solid spheres

potable water

water that is safe for humans to drink

pure substance

a substance that contains only one compound or element

Rf value

the distance travelled by the dissolved substance / the distance travelled by the solvent

sedimentation

a process used in water treatment where suspended solids fall to the bottom of a container and form a sediment, allowing for the to be easily removed

simple distillation

where a solution is heated so that only the liquid with the lowest boiling point evaporates, and this gas is condensed in a condenser before being collected as a liquid

solid

the state of matter where the particles hold a regular arrangement and have the least amount of energy

state symbols

the symbols used in chemical equations to denote the states of the chemicals reacting

stationary phase

the non-moving phase which the mobile phase passes over during chromatography

waste water

water from industrial, agricultural, domestic and commercial activity that needs to be treated before it is potable