Topic 2

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

  Chlorination
• A process used to separate substances in a mixture. Separation of the substances depends on distribution between a mobile phase and a stationary phase.

  Chromatography
• A separation technique to obtain soluble solids from solutions. The process involves heating the solution until crystals start to form, leaving the solution to cool and then filtering the formed crystals from the solution.

  Crystallisation
• A separation technique used to separate an insoluble solid from a solution.

  Filtration
• A process used to separate a mixture of liquids. The liquids have different boiling points so can be separated in to different fractions with a fractioning column.

  Fractional distillation
• The state of matter where the particles have the most energy. The particles are relatively spread out an move randomly in all directions.

  Gas
• Water which collects in rocks that then trap the water underground.

  Ground water
• The state of matter where the particles are arranged randomly and close together. The particles are able to move past each other.

  Liquid
• Data which can be used to evaluate the purity of a substance. A pure substance should have sharp melting point.


  Melting point data
• Contains at least two different elements or compounds which are not chemically bonded together.

  Mixture
• The fluid which moves through the chromatography system, carrying the mixture which is to be separated.

  Mobile phase
• A type of chromatography which uses paper as the stationary phase and a solvent as the mobile phase. The solvent carries the mixture up the paper where the substances in the mixture then separate, depending on how soluble they are in the mobile phase.

  Paper chromatography
• The theory which models the three states of matter by representing the particles as small sold spheres, it can help explain melting, boiling, freezing and condensing.

  Particle theory
• A substance which contains only one compound or element.

  Pure substance
• A value used in chromatography which is calculated as the distance travelled by the dissolved substance divided by the distance travelled by the solvent. It can be used to identify substances within a mixture.

  Rf value
• A process used in water treatment to remove solids from the water. Suspended solids will fall to the bottom of the container and form a sediment, allowing them to be easily removed.

  Sedimentation
• A separation technique used to separate a liquid from a solution. The solution is heated so that only the liquid with the lowest boiling point evaporates. This gas is then condensed in a condenser before it is collected as a liquid.

  Simple distillation
• The state of matter where the particles hold a regular arrangement and have the least amount of energy.

  Solid
• The nonmoving phase which the mobile phase passes over during chromatography.

  Stationary phase
• Water from industrial, domestic, agricultural and commercial activity. It requires treatment before it is potable.

  Waste water