Review:
Organic chemistry is a branch of chemistry that focuses on the study of carbon compounds, excluding carbon oxides and carbonates. Carbon has the unique ability to form four covalent bonds, allowing it to create a wide range of compounds. These compounds, known as hydrocarbons, are composed of carbon and hydrogen atoms only.
Hydrocarbons are classified into three groups based on the type of bond between carbon atoms in their molecules: alkanes, alkenes, and alkynes. Alkanes are hydrocarbons with carbon atoms linked by single covalent bonds. They are considered saturated hydrocarbons since they only have single bonds.
Crude oil is a major natural source of alkanes, along with natural gas and biogas. Fractional distillation is used to separate the different components of crude oil based on their boiling points. Each fraction has different uses, and as the number of carbon atoms in the chain increases, the boiling point, viscosity, and intensity of color also increase, while flammability decreases.
Alkanes can undergo cracking, a process that breaks down long-chain alkanes into smaller chain alkanes, alkenes, and hydrogen. There are two types of cracking: thermal cracking, which occurs at high temperatures, and catalytic cracking, which occurs at lower temperatures in the presence of a catalyst.
Nomenclature of alkanes involves using a suffix (-ane) and a prefix numeral to indicate the number of carbon atoms in the chain. Isomerism in alkanes refers to compounds with the same molecular formula but different structural formulae. The physical properties of isomers, such as boiling points and density, may differ while their chemical reactions remain similar.
Preparation of alkanes can be done through laboratory reactions, such as the reaction between sodium hydroxide and an appropriate alkanoate. Alkanes have various physical properties, and as the carbon chain length increases, their boiling points and viscosity also increase.
In summary, understanding the basics of organic chemistry, hydrocarbons, and alkanes is crucial. This knowledge helps in identifying their structure, naming, properties, and methods of preparation. By studying these topics, one can gain a comprehensive understanding of the fascinating world of organic chemistry.
