The order of basicity of amines in gaseous state is :
The order of basicity of amines in gaseous state is :
$1^{\circ}>2^{\circ}>3^{\circ}>\mathrm{NH}_3$
$3^{\circ}>2^{\circ}>\mathrm{NH}_3>1^{\circ}$
$3^{\circ}>2^{\circ}>1^{\circ}>\mathrm{NH}_3$
$\mathrm{NH}_3>1^{\circ}>2^{\circ}>3^{\circ}$
Solution
The correct order of relative basicity of amines in the gas phase is $3^{\circ}>2^{\circ}>1^{\circ}>\mathrm{NH}_3$ The alkyl group releases electron and thus, tends to disperse the positive charge of the alkyl ammonium ion and therefore stabilises it. Since, $\mathrm{NH}_4{ }^{+}$(from $\mathrm{NH}_3$ ) has no such alkyl group, it is not stabilised to such an extent as alkylammonium ion.