Carbon Compounds

(a)

(b)

(c)

(d)

(a) C₃H₈

Propane (C₃H₈) has no isomers. There is only one possible structure for propane:

(b) C₄H₁₀

(c) C₃H₄

Only one structure is possible

The phenomenon in which compounds having different structural formulae have the same molecular formula is called structural isomerism

Example: Molecular Formulae= C4H10

The chemical bond formed by sharing of two valence electrons between the two atoms is called the covalent bond. Examples:- H₂

The atoms of the elements such as halogen, oxygen, nitrogen substitute one or more hydrogen atoms in the hydrocarbon chain and thereby the tetravalency of carbon is satisfied. The atom of the element which is a substitute for hydrogen is referred as a hetero atom in carbon compounds.

A heteroatom is any atom that is not carbon or hydrogen. Example:

Note: Typical heteroatoms are nitrogen, oxygen, sulfur, phosphorus, chlorine, bromine, and iodine.

The compounds acquire specific chemical properties due to the hetero atoms or the groups. These hetero atoms or the groups containing hetero atoms are called functional groups.

Examples:- alcohol(-OH), aldehyde( – CHO)

The major functional groups are shown below:

The valencies of all the atoms are satisfied by the single bonds. Such compounds are called saturated compounds. Saturated hydrocarbons are called alkanes.

Examples:- butane, methane

The following are the structures of alkanes:

The compound in which the valency of all the atoms is either satisfied by the double or triple bond is called unsaturated hydrocarbon.

Examples:- ethene, propyne

The polymers which are formed by the repetition of a single monomer is called as homopolymers.

Examples:- Polyethylene, Teflon etc.

The smallest unit that repeats regularly to form a polymer is called monomer.

Example: Polyvinyl is formed from the monomer 'vinyl chloride'

Chemical reaction that involves the gaining of electrons by one of the atoms involved in the reaction.

Example: conversion of an aldehyde to alcohol.

Substances that can give oxygen to other substances are called oxidants or oxidizing agents.

Examples:- potassium permanganate, potassium dichromate.

Butane

Explanation: The parent chain consists of Four carbons and the valency of all the atoms is satisfied by single bond so It is a saturated hydrocarbon with the name Butane.

Propane-2-ol

Explanation: (i) The parent chain consists of three carbons so 'prop' is used and the numbering can be done from either left to right or right to left since this a symmetrical molecule.

(ii) On the second carbon, OH group is present which means alcohol group so the suffix used is 'ol'

Propanoic Acid

Explanation: (i) The parent chain consists of three carbons so the prefix 'propan' is used.

(ii) There is also a presence of COOH group indicating acid so the suffix used in this case is ' oic acid'

Ethanamine

Explanation: (i) The parent chain consists of two carbon atoms so the prefix 'eth' is used.

(ii) The presence of NH2 groups indicates the presence if amine and the same is used as the suffix

Ethanal

Explanation: (i)The parent chain consists of two carbon atoms so the prefix used is 'Eth'

(ii) There is also a presence of aldehyde group I.e. CHO so the suffix used is 'al'.

But-2-one

Explanation: (i)The parent chain consists of four carbon atoms so the prefix used is 'But'

(ii) There is also a presence of ketones group I.e. CO so the suffix used is 'one' and 2 is indicating the position of the ketone group.

(a) Oxidation Reaction

Propanol is oxidized to propanoic acid

(b) Combustion reaction

Propane in the presence of air gives carbon dioxide and water.

(c) Addition Reaction

Bromine attacks on the double bond to give Vic. Dihalide.

(d) Substitution reaction

Chlorine replaces the hydrogen and the second chlorine forms the byproduct HCl.

(e) Dehydration reaction

Butanol reacts in the presence of acid to give alkene with the removal of water.

(f) Neutralization reaction

Ethanoic acid in pre

sence of base NaOH gives salt and water.

(g) Esterification reaction

Acetic acid and methanol reacts to give ester (methyl methanoate) as the product.

CH₃CH₂CH₂COOH

Carbon is able to form large number of compounds due to the property of catenation.

The atomic number of carbon = 6.

The two electrons are in the inner orbit, while the other four are valance electrons—outer electrons that are available for forming bonds with other atoms.

Due to this, carbon can form large number of compounds and catenation is the reason for the existence of large number of carbon compounds.

The saturated hydrocarbons are classified into three types:-

(i) Straight chains:- The carbon atoms are joined in a straight chain with single bond.

(ii) Branched chain:- Some carbon atoms are branched to other carbon atoms.

(iii) Rings:- Carbon atoms forms the rings.

Four functional groups are:-

(i) Alcohol

Example: Propan-2-ol

(ii) Aldehyde

Example: methanal

(iii) Carboxylic acid

Example: Butanoic acid

CH₃CH₂CH₂COOH

(iv) ketones

Examples:- butanone

(i) Ethanamine containing nitrogen as the hetero atom

(ii) Alchol containing oxygen as the hetero atom

Example: propan-2-ol

(iii) 2-chlorobutane containing Chlorine as the hetero atom.

Three Natural polymers are:-

Vinegar is liquid consisting of water and acetic acid and other Trace chemicals which includes flavoring.

Uses of Vinegar:-

(i) eliminates odors

(ii) Kill bathroom germs

(iii) freshen up the fridge

Gasohol is a mixture of petrol and alcohol used as an alternative fuel for cars and other vehicles.

Catalyst is a substance that causes a chemical reaction to occur but is not itself involved in the reaction.

Example: formation of ammonia

N₂ + 3H₂→ 2NH₃

Catalyst used is iron and molybednum.