How is ozone prepared from oxygen ? Explain its reaction
i) `C_(2)H_(4)` ii) KI ii) Hg iv) PbS

Explanation

i) PbS is oxidised to `PbSO_(4)`
`PbS (s) + 40_(3) (g) to PbSO_(4) + 4O_(2)`
ii)
iii) Silver metal is blackened. This is due to oxidation of the metal first to its oxide and subsequent reduction to the metal.
`2Ag + O_(3) to Ag_(2) O + O_(2)` (oxidation)
`Ag_(2) O + O_(3) to 2Ag + 2O_(2)` (reduction)
iv) `Hg_(2) O` formed sticks to the glass surface and mercury loses its meniscus due to dissolution of `Hg_(2) O` in Hg. This is called tailing of mercury.
`2Hg + O_(3) to Hg_(2) O + O_(2)`