Organic Chemistry

Nitrogen Cycle

The nitrogen cycle is the biogeochemical cycle that describes the gradual transformation of nitrogen and nitrogen-containing compounds in nature. It is the means by which the supply of nitrogen is distributed in nature. The Earth’s atmosphere, containing about 79percent nitrogen, constitutes the largest pool of nitrogen. Nitrogen is crucial to all life processes on earth. […]

Organic Chemistry

Carbon Cycle

The carbon cycle is the series of interconnected changes by which carbon is being continuously circulated among the natural compartments of atmosphere, biosphere, hydrosphere, geosphere and pedosphere. There are four major reservoirs involved in the carbon cycle. These are the plants, the terrestrial biosphere (fresh water systems and non- living organic material), the oceans (where […]

Organic Chemistry

Environmental Chemistry

Environmental Chemistry is the study of chemical substance present in the environment which are induced by human’s activities. These activities may be felt on a local scale, through the presence of urban air pollutants or toxic substances arising from a chemical waste site, or on a global scale, through depletion of stratospheric ozone or global […]

Organic Chemistry

Reduction of Aldehydes and ketones

Addition of organometallic reagents to Aldelydes and ketones Organometallic reagents (RLI or RMgX) react with aldehydes and ketones to give alcohols. Use of RLi              Reaction with RMgX In this reaction the intermediate alkylmagnesium halide is hydrolysed using dilute acid or aqueous ammonium chloride in the case of tertiary alcohols   […]

Organic Chemistry

Hydration of alkene

  This reaction is simply the addition of water molecule to the alkene to form the corresponding alcohol. It involves the addition of concentrated tetraoxosulphate (VI) acid first to the alkene to give alkyl hydrogen tetraoxosulphate (VI) which when treated with water (hydrolysis), gives an alcohol.   For example, the formation of ethanol:   CH2 […]

Organic Chemistry

Hydrolysis of halogenoalkanes

  This reaction is suitable for the preparation of primary, secondary and tertiary alcohols. All halogenoalkane when heated under reflux with aqueous potassium hydroxide solution are hydrolysed to yield an alcohol       RX + KOH     ROH +     X– reflux       Where X= I , Br , Cl     and R= alkyl group   The ease of […]

Organic Chemistry

Physical Properties of Alcohols

Physical Appearance Most simple alcohols are liquid at room temperature. Alcohols with more than twelve carbon atoms are waxy solid at room temperature. Melting and boiling point Like the parent hydrocarbon, the boiling points among the alcohols increase steadily with increase in the number of carbon atoms. The boiling point of alcohols are very high […]

Organic Chemistry

Naming Alcohols

a. Common names Simple alcohols are often called by their common names which consists of the name of the alkyl group to which the –OH group is attached followed by the word ‘alcohol’.   For example,                CH3OH     CH3CH2OH     CH3CHOH Methyl alcohol     Ethyl alcohol     | CH3 Isopropyl alcohol   b. IUPAC names In […]

Organic Chemistry

Classes of Alcohols

Alcohols can contain one or more hydroxyl group. It could be: Monohydric – contain only one hydroxyl group. For example, ethanol.   CH3-CH2-CH2-OH Ethanol   Dihydric- contain two hydroxyl groups. For example ethane-1,2-diol.   CH2 – CH2     |     |     OH     OH   Trihydric- contains three hydroxyl groups. For example, propane-1, 2, 3-triol. Generally with more […]