Which of the following elements is $NOT$ a member of group $16$ of the periodic table?

An amorphous solid $'A'$ burns in air to form a gas $'B'$ which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aqueous $KMnO_4$ solution and reduces $Fe^{3+}$ to $Fe^{2+}$. Identify the solid $'A'$ and the gas $'B'$ and write the reactions involved.

Provide information about simple oxides.

How does $SO_2$ gas behave when it is moist?

Which of the following statements is $NOT$ correct about ozone?

Nitrogen dioxide $(NO_2)$ and sulphur dioxide $(SO_2)$ have some properties in common. Which property is shown by one of these compounds,but not by the other?