Topic 3 Flashcards
compound
A substance made of two or more elements chemically bonded together
Mixture
Two or more chemical substances found together but not chemically bonded.
element
A chemical substance that cannot be broken down into simpler substances. It is composed as one type of atom only.
anhydrous
Salts that do not contain water of crystallisation often resulting from hydrated salts being heated.
hydrocarbon
A compound made of hydrogen and carbon only.
petroleum
The mixture of hydrocarbons found naturally formed by the decay of marine organisms. Also known as crude oil.
Solvent
A liquid substance within which a solid can dissolve.
solute
A soluble solid that has dissolved in a solvent.
residue
The solution that passes through the filter in filtration.
filtrate
The solution which passes through the filter during filtration.
chromatography
A method used to separate and identify substances by dissolving them in a solvent and allowing them to be carried by the solvent through a sheet of filter paper. The dissolved solutes are deposited along the sheet of paper according to their solubility and mass.
soluble
able to be dissolved
Locating agent
A chemical substance that will react with the solute(s) separated in chromatography to produce a coloured substance. Locating agents are used to identify colourless compounds separated by chromatography.
Rf equation
Rf=distance travelled by substance
———————————————-
distance travelled by solvent
Fractional distillation
A chemical process that describes heating and separating substances by distillation into more useful products (or fractions) based on their boiling points. It is used in the refining of crude oil.
filteration
A purification method used to remove an insoluble solid from liquids by pouring through a filter, such as filter paper.
crystallisation
A purification method used to obtain solid dissolved in a solution. As the liquid part of the solution cools and becomes denser, there is less space for the solid particles to occupy. These particles are excluded from the liquid and form crystal arrangements on the side of the vessel containing them.
Distillation
A purification method used to separate a mixture of liquids by boiling and condensing.