Chemistry Revision Cards

The general formula of the alkenes containing one C=C bond is 

C_nH_2n

Complete combustion of an alkene forms carbon dioxide and water

Alkenes react with halogens, hydrogen and water (steam) by adding atoms across the C=C bond, forming a saturated molecule

The homologous series of alchols contains the -OH functional group

The homolohous series of carboxylic acids contains the -COOH functional group

The homologous series of esters contains the -COO- functional group

Alcholos are used as solvents and fuels, and ethanol is the main alcohol in alcoholic drinks

Alcohols burn in air, forming carbon dioxide and water

Alcohols react with sodium metal to form a solution of sodium alkoxide and hydrogen gas is given off

Ethanol can be oxidised to ethanoic acid, either by chemical oxidising agents or by the action of microbes in the air, ethanoic acid is the main acid in vinegar

Solutions of carboxylic acis have a PH value of less than 7. Carbonates generally fizz in solutions of carboxylic acids, releasing carbon dioxide gas

Aqueous solutions of carboxylic acids, which are weak acids, have a higher PH value than solutions of strong acid with the same concentration

Esters are made by reacting a carboxylic acid with and alcohol, in the presence of a strong catalyst

Esters are volatile, fragrant compounds used in flavouring and also perfumes

The difference between strong and weak acids is that strong acids are likely to fully ionize whereas weak acids are not. Although a common misconception, when used in regards to the strength of an acid, the terms “strong” and “weak” do not refer to the terms “concentrated” and “diluted."  

Because strong acids are more likely to ionize and dissociate, their dissociation reactions are considered to be irreversible. 

Stronger acids have larger acid dissociation constants (Ka) than weak acids.

All acids have a pH between one and seven. However, when of equal concentrations, strong acids have lower pH’s than weak acids.

Examples of strong acids are hydrochloric acid, sulfuric acid, and hydrobromic acid.

Examples of weak acids are acetic acid and formic acid.