Arrange the compound of each set in order of decreasing reactivity towards (S_(N^(2))) displacement. (a). 2-bromo-2-methylbutane,1-Bromopentane,2-Bromopentane (b). 1-Bromo-3-methylbutane,2-Bromo-2-methylbutane, 2-Bromo-3-methylbutane (c). 1-Bromobutane, 1-Bromo-2,2-dimethylpropane, 1-Bromo-2-methylbutane, 1-Bromo-3-methylbutane.

Arrange the compound of each set in order of decreasing reactivity tow

1.	Arrange the compound of each set in order of decreasing reactivity towards (S_(N^(2))) displacement. (a). 2-bromo-2-methylbutane,1-Bromopentane,2-Bromopentane (b). 1-Bromo-3-methylbutane,2-Bromo-2-methylbutane, 2-Bromo-3-methylbutane (c). 1-Bromobutane, 1-Bromo-2,2-dimethylpropane, 1-Bromo-2-methylbutane, 1-Bromo-3-methylbutane.
Answer» Solution :The REACTIVITY of a particular haloalkane towards `S_(N^(2))` reaction is inversely proportional to the steric HINDRANCE around the carbon atom involved in C-X BOND. More the steric hindrance, lesser will be the reactivity. In the light of this the DECREASING ORDER of reactivity in all the three cases is as follows: