Question

explain addition reaction of alkanes?

Answer 1

Unsaturated hydrocarbons such as alkenes and alkynes are much more reactive than the parent alkanes. Theyreact rapidly with bromine, for example, to add a Br2 molecule across the C=C double bond. ... When Br2 in CCl4 is mixed with a sample of analkane, no change is initially observed.
In the absence of a spark or a high-intensity light source, alkanes are generally inert to chemical reactions. However, anyone who has used a match to light a gas burner, or dropped a match onto charcoal coated with lighter fluid, should recognize that alkanes burst into flame in the presence of a spark. It doesn't matter whether the starting material is the methane found in natural gas,

CH4(g) + 2 O2(g) CO2(g) + 2 H2O(g)

the mixture of butane and isobutane used in disposable cigarette lighters,

2 C4H10(g) + 13 O2(g) 8 CO2(g) + 10 H2O(g)

the mixture of C5 to C6 hydrocarbons in charcoal lighter fluid,

C5H12(g) + 8 O2(g) 5 CO2(g) + 6 H2O(g)

or the complex mixture of C6 to C8hydrocarbons in gasoline.

2 C8H18(l) + 25 O2(g)  16 CO2(g) + 18 H2O(g)

Once the reaction is ignited by a spark, these hydrocarbons burn to form CO2 and H2O and give off between 45 and 50 kJ of energy per gram of fuel consumed.

In the presence of light, or at high temperatures, alkanes react with halogens to form alkyl halides. Reaction with chlorine gives an alkyl chloride.

Answer 2

Unsaturated hydrocarbons such as alkenes and alkynes are much more reactive than the parent alkanes. Theyreact rapidly with bromine, for example, to add a Br2 molecule across the C=C double bond. ... When Br2 in CCl4 is mixed with a sample of analkane, no change is initially observed