Which of the following are secondary radicals?
$(1) \ CH_3 - \dot{C}H - C_2H_5$
$(2) \ CH_2 = \dot{C} - CH_3$
$(3) \ CH_2 = CH - \dot{C}H_2$
$(4) \ (CH_3)_2 \dot{C}H$

Among the following carbocations:
$(I)$ $Ph_{2}\stackrel{+}{C} CH_{2} Me$
$(II)$ $Ph CH_{2} CH_{2} \stackrel{+}{C} HPh$
$(III)$ $Ph_{2} CH \stackrel{+}{C} HMe$
$(IV)$ $Ph_{2} C(Me) \stackrel{+}{C} H_{2}$
The order of stability is:

$2-$chloropentane on halogenation with chlorine gives $2,3-$dichloropentane. What will be the structure of the free radical species formed in the reaction?

Which of the following carbocations is most stable?
$A) (CH_3)_2CH-CH^+-CH_3$
$B) (CH_3)_2C^+-CH_2CH_3$

Which of the following has maximum stability?

Which of the following is the most stable among the given ions?