Question

There are different kinds of isomers, describe them.

Name FIVE functional groups and list a property of each one.

Why is carbon so important to life on earth?

Answer 1

ISOMERS- An isomer is an molecule which have the same molecular formula but have different chemical structure.Isomers are those which contain same number of atoms of each element but hav their different arrangements of their atoms of each element.There are two main forms of isomerism Structural isomerism and stereoisomerism

Structural isomerism-Structural isomerism is also known as constitutional isomerism and it is a form of isomerism in which the molecules have same molecular formula and have different bonding patterns or atomic organisation is known as structural isomerism.structural isomerisms have same molecular formula but have different structures.they are divided in to further.

1.Chain isomerisms- Chain isomerisms is also known as Nuclear or Skeleton isomerism. This type of isomerisms is due to the difference in the nature of the carbon chain i.e straight or branched which forms the nucleus molecule.It means they have molecular formula but they create different chain structures.

2. Position isomerisms- It is due to the difference in the position of the side chain atom or group ag an unsaturated linkage in the same carbon chain.these are those in which have same molecular formula but their position has changed is known as position isomerism.For ex- 1,1 chloro benzene or 1,3 chloro benzene.

3. Functional isomerism- This type of isomerism is due to the difference in the nature of functional group present in the isomers it means their molecular formula is same but the functional group is different is known as functional group isomerisms.

4. Tautomerisms- tautomers are the compound of isomers which differ only in the position of the electrons and proton and carbon skelton compound doesnot changed.A reaction which involves a simple proton transfer in an intermolecular is known as tautomerism.For ex keto form chnaged in to enol form.

STEREOISOMERISMS- When isomers have the same structural formula but different in their arrangement of atoms or groups in space within molecules is known as stereoisomerism.They have same structural formula but they have different configuration.stereoisomerisms further divided in to two parts;

1. Geometrical isomerisms- The isomers which have same structural formula but different in the spaital arrangement of the groups around a double bond are known as geometrical isomers and the phenomenon is known as geometrical isomerisms.in the cis isomers the group lie on the same side but in trans isomers group lie in the opposite side.

2. Optical isomerisms- The isomerisms which have different arrangement of atoms or groups in space resulting in the two isomers which are mirror image of each other.Optical isomerisms contain asymmetrical carbon atom in their molecules in this carbon atom attached to four different atoms or groups.The isomers which rotates the plane polarised light to left is known as laevo(l) while when palne polarized light rotates left is known as dextro(d).

FIVE FUNCTIONAL GROUPS ARE ALCOHOLS (-OH) , ETHERS(-R-O-R-), KETONES (-RC=O-R-), ALDHEHYDES (-R-CHO), CARBOXYLLIC ACID (-COOH)

1. Properties of Alochol- Alcohol is soluble in water and this is due to the presence of hydroxyl group in the alcohol which is able to form hydrogen bond with water molecules.as the length of the hydrocarbon chain increases the solubility in water decreases, smaller the chain more the solubility in water.

2. Properties of Ether- Ether molecules are miscrible in water and they have net dipole moment due the polarity of c-o bonds.

3. Properties of Ketones- Ketones are soluble in water but their solubility is decreases with the increase in the length of the chain.

4. Properties of Aldhehyde- The boiling point of aldhehydes is increases with increase in their molecular weight.its boiling point depends upon the strength of intermolecular forces.

5. Properties of Carboxyllic group- It has a electronegative oxygen double bond to a carbon atom as aresult there is increase in the polarity of a bond. A compound which have carboxyllic group have higherr melting point,hydrophyllic centres and boiling point.

CARBON IS SO IMPORTANT TO LIFE ON EARTH BEACAUSE OF THE FOLLOWING REASONS

1. Most of the living things are made of the carbon. Living things needs carbon for their survival,reproduction and for growing.

2. Carbon is one of the finest resource that cycles through the earth in many forms.thi make carbon available to living organisms and remain in balance with other chemaical reactions in the atmoshphere and in aquatic system like ponds,lakes and oceans.