(N/A) Definition: Ozonolysis of alkenes involves the addition of an ozone molecule to an alkene to form an ozonide,followed by the cleavage of the ozonide using $Zn/H_{2}O$ to yield smaller carbonyl molecules. This reaction is highly useful in detecting the position of the double bond in alkenes or other unsaturated compounds.
$(b)$ General reaction:
$R_{2}C=CR_{2} + O_{3}$ $\xrightarrow{CH_{2}Cl_{2}/CHCl_{3}/CCl_{4}, \approx 200K} \text{Ozonide}$ $\xrightarrow{Zn, H_{2}O} R_{2}C=O + O=CR_{2} + H_{2}O_{2}$
$(c)$ Example: Ozonolysis of propene:
$CH_{3}-CH=CH_{2} + O_{3}$ $\xrightarrow{CCl_{4}} \text{Propene ozonide}$ $\xrightarrow{Zn, H_{2}O} CH_{3}CHO (\text{Ethanal}) + HCHO (\text{Methanal}) + H_{2}O_{2}$