Hydrocarbons

Question 1

Physical properties of alkanes

Answer 1

• Algens are almost nonpolar molecules because of the covalent nature of sea and ch bonds and due to very little difference of electronegativity between C and H.
• They possess weak waterfall forces due to the weak fundamental forces the first four members C1 to C4 are gasses C-5 to C-17 are liquid and greater than C18 compound are solid.
• They are colorless and Orderless.
• Polar substances are soluble in polar solvents whereas nonpolar substances are soluble in nonpolar solvents that is like dissolves like for example petrol and lower fractions of petroleum are used for dry cleaning of clothes to remove grease stains.
• There is a steady increase in boiling point with increase in molecular mass this is because the intermolecular randomness forces increase with the increase of molecular size a surface area of the molecule.

Question 2

Confirmations

Answer 2

Alkins containing sea cinema C Sigma Bond this permits free rotation about the cc single bond this rotation results in different spatial arrangement of atoms in space which can change into another such spatial arrangement of atoms which can be converted into another by rotation round C single bot C single bond are called confirmations or conformers.

Question 3

Newman projection

Answer 3

In this method the molecule is viewed from the front along the carbon bond axis the two carbon atoms forming the Sigma Bond are represented by the two circles first up one behind the other so that only the front carbon is seen. The other carbon atom is shown by a point miras the carbon further from the eye is represented by the circle. Therefore the C single 1H board of the front carbon are depicted from the center of the circle while the scene H bond of the back carbon are drawn from the circumference of the circle at an idle of 120 degrees at each other.

Question 4

Alkins are also known

Answer 4

olefins
oil forming

Question 5

Properties of geometric al isomers

Answer 5

• The sys form of alkene is so found to be polar than the transform
• Dipole moment of the transform is almost zero

Question 6

Lindlar’s catalyst

Answer 6

Partially deactivated paradised charcoal is known as LindLars catalyst.

Question 7

Physical properties of alkene

Answer 7

• the first three members are gasses, the next 14 are liquids, and the higher ones are solids.
• ethene is a colorless gas with a faint sweet smell.
• All other alkins are colorless and orderless, insoluble in H2 but fairly soluble in nonpolar solvents like benzene, petroleum ether etc
• They show a regular increase in boiling point with increase in size.
• straight train alkenes have higher boiling point than isomeric branched chain compounds

Question 8

test for unsaturation

Answer 8

The reddish orange color of bromine solution in ccl 4 is discharged when bromine adsorb to unsaturation site this bromide form is colorless.

Question 9

An alkene a contains a three cc 8CH sigma bonds and one cc pi bond. and also analysis gives two moles of an aldehyde of molar was 44U write the iopac name of A

Answer 9

But-2-ene

Question 10

Physical properties of alkyne

Answer 10

• the first three members of alkynes are gasses, next eight are liquids and higher ones are solids.
• archives are colorless odorless except ethane first up it has a characteristic order.
• Alkynes are immiscible with water but soluble organic solvents like ether, ccl for, C6H6.
• The melting point and boiling point and density increase with increase in molar mass