a) 2- Methylpropene can be converted into isobutyl bromide by hydrogen bromide. Write the condtion.
b) Ehyne and its derivatives will give precipate with ammoniacal silver nitrate solution. Mention the condition under which this statement is true.

Explanation

a) 2-Methylpropene reacts with HBr in presence of peroxide as the addition occurs through anti-Markownikoff's rule.
`CH_(3)-overset(CH_(3))overset(|)C=CH_(2)+HBroverset("Peroxide")toCH_(3)-overset(CH_(3))overset(|)(CH)-CH_(2)Br`
b) Only those derivatives of ethyne will give white precipitate with ammoniacal siler nitrate whic posses acidic hydrogen atom, i.e., `R-C=-CH`. The derivatives `R_(1)C=-C-R_(2)` do not give precipitate with ammonicial silver nitrate.