Question

give any two methods of preparation of n-butane​

Answer 1

Answer:

Explanation:

Following are two well know methods for preparation of n-butane:

1) Wurtz reaction

On reaction of R-X with Sodium in presence of ether, alkane is produced. In order to produce n - butane, we can use reaction between ethyl bromide with sodium as follows:

CH₃CH₂Br + 2Na + CH₃CH₂Br  ⇒ CH₃CH₂CH₂CH₃ + 2NaBr

2) Addition of Hydrogen to alkene in presence of catalyst such as Pt, Pd.

On addition of hydrogen to an alkene, the double bond of the compound breaks and corresponding alkane is obtained.

CH₃ - CH₂ - CH = CH₂   +  H₂  ⇒  CH₃ - CH₂ - CH₂ -CH₃

Answer 2

Explanation:

n- Butane molecular formula of compound is C4H10

Butane is a colourless gas.

Preparartion of n-Butane :

From Hydrogentaion of oils / Addition reaction

Here Butene is added with Hydrogen in presence of catalyst called as Ni

to produce Butene.

Double bonds are broken into single bonds

                      catalyst

C4H8  + H2 ------------------> C4H10

                        Ni

Here unsaturated hydrocarbon compounds are made into saturated hydrcarbon

Kolbe's electrolysis process:

During this reaction Carbon dioxide is released at anode along with formation of alkanes.

General Equation :

2R-COONa (on Electrolysis) → R - R + 2CO2 + H2 + NaOH

During this reaction on electrolysis, sodium butanoate will give butane,  

CO2 at anode along with NoaH

2CH3CH2CH2-COONa------------------>CH3CH2CH2CH3+2CO2+NaOH+H2