The total number of chiral molecules formed from one molecule of P...

The Ozonolysis mechanism proceeds via an oxidative cleavage reaction. The ozone not only breaks the carbon pi bond but also the carbon-carbon sigma bond. It involves the attack of ozone on the given reactant to form an ozonide. To eliminate the oxygen in this intermediate stage, zinc dust is employed (since it forms zinc oxide with oxygen).

In reductive ozonolysis the ozonide is treated with mild reducing agents such as dimethyl sulfide and zinc metal with water. The ozonide is reduced as shown below.

$∴$ Two chiral molecules are obtained.