White silver surface turns black when $O_3$ is passed over it. This is due to the formation of

What are the values of electron gain enthalpy in groups $16$ and $17$? How do they change?

Which of the following is used as a photoconductor in xerox machines?

Choose the correct statements from the following:
$A$. All group $16$ elements form oxides of general formula $EO_2$ and $EO_3$ where $E=S, Se, Te$ and $Po$. Both the types of oxides are acidic in nature.
$B$. $TeO_2$ is an oxidising agent while $SO_2$ is reducing in nature.
$C$. The reducing property decreases from $H_2S$ to $H_2Te$ down the group.
$D$. The ozone molecule contains six lone pairs of electrons.
Choose the correct answer from the options given below:

Which of the following dissociates to give ${H^{+}}$ most easily?

Which of the following statements is correct about $O_2$ and $O_3$ molecules?