Natural Rubber

Natural Rubber Natural Rubber Natural rubber is a natural polymer. Latex is a milk like liquid that flows out after the bark of the rubber tree is cut. Latex is mixture of rubber particles and water. Formula of natural rubber is (C5H8)n, where n is about 10,000. Monomer of natural rubber is C5H8, known as … Read more

Fats and Oils

Fats and Oils Oils and fats belong to a group of organic compounds known as lipids. Oils and fats are natural occurring esters. Fats are found in animals. Oils are found in both animals and plants. Structure of the Molecules Differences between Oils and Fats Fats are solids at room temperature while oils are liquids … Read more

Ester

Ester Esters are non-hydrocarbon organic compounds containing carbon, hydrogen and oxygen. It is formed when a carboxylic acid reacts with an alcohol. General Formula: CmH2m + 1COOCnH2n + 1 wherem = 0, 1, 2, 3n = 1, 2, 3 Example Ester  Formula   Methyl methanoate(m=0, n=1)  HCOOCH3  Ethyl methanoate(m=1, n=1)  CH3COOCH3  Ethyl ethanoate(m=1, n=2)  CH3COOC2H5  Propylethanoate(m=2, … Read more

Chemical Properties of Carboxylic Acids

Chemical Properties of Carboxylic Acids Ethanoic acid is a weak monoprotic acid. As such, its chemical properties are similar to acids such as hydrochloric acid, nitric acid and sulphuric acid. Ethanoic acid can react with: base metal carbonate metal alcohol Reactions of Carboxylic Acids with Reactive Metals Carboxylic acids react with the more reactive metals … Read more

Preparing Carboxylic Acids

Preparing Carboxylic Acids Making Carboxylic Acids by Oxidising Primary Alcohols  Alcohols can be oxidised to carboxylic acids using potassium dichromate(VI) solution in the presence of dilute sulphuric acid. Chemical Equation below represents the reaction.  C2H5OH+2[O] → CH3COOH + H2O The figure below shows the apparatus set up to prepare ethanoic acid. The mixture is heated … Read more

Physical Properties of Carboxylic Acids

Physical Properties of Carboxylic Acids Boiling points The greater the number of carbons in the molecule, the higher the boiling point of a carboxylic acid. The boiling points of carboxylic acids are higher than the alcohols of same number of carbons. Solubility in water The small molecule carboxylic acid such as methanoic acid and ethanoic … Read more

Carboxylic Acid

General Formula: CnH2n+1COOH, n = 0, 1, 2, ….. Functional Group: Carboxyl First 3 Members: Carboxylic Acids are weak acid. The functional group of carboxylic acids is carboxyl group. When dissolve in water, the carboxyl group will ionise to produce a hydrogen ion. Naming Carboxylic Acids All carboxylic acid names end with the suffix ‘oic’. For … Read more

Chemical Properties of Alkohol

Chemical Properties of Alcohol Combustion of Alcohol As the hydrocarbon, alcohols undergo combustion with the presence of oxygen to produce carbon dioxide and water. Combustion of alcohol produces less soot compares to combustion of alkanes and alkenes due to the presence of oxygen in the –OH group. Owing to the presence of the –OH group, … Read more

Preparing Alkohol

Preparing Alcohol Alcohols can be prepared by using 2 methods Hydration of alkene Fermentation Hydration of Alkene When we discuss the chemical properties of alkenes, we have learned that, when alkenes undergo addition reaction with steam, alcohol will be produced. (see hydration of alkenes). Equations below shows the hydration of ethene and propene to produce ethanol and … Read more