Question

Select correct statement (s):
A. Alkali metals ozonides are coloured and paramagnetic
B. Alkali metal-ozonides are colourless and diamagnetic
C. Sesquioxides of alkali metal are peroxides superoxides $$(M^{+}{)}_4({O_2}^{2-})({O_2}^{-}{)}_2$$
D. Sesquioxides are paramagnetic due to presence of superoxide ion ${O_2}^{-}$

Answer 1

Hint: Ozonide is an unstable and reactive polyatomic anion ${O_3}^{-}$ analog of ozone. Sesquioxides is an oxide containing three atoms of oxygen and two atoms of another element.

Complete step by step answer:
Firstly, we need to know about ozonides and sesquioxides.
Ozonide is the unstable, reactive polyatomic anion ${O_3}^{-}$ analog of ozone or any of several classes of organic peroxide compounds similarly formed by the reaction of ozone with an unsaturated compound. Inorganic ozonides are dark red ionic compounds containing the reactive ${O_3}^{-}$ anion. The anion has a bent shape of the ozone molecule.
Inorganic ozonides are formed by burning potassium, rubidium or caesium in ozone or by treating the alkali metal hydroxide with ozone. Also, if potassium is left undisturbed in air for years it accumulates a covering of superoxide and ozonide. They are very sensitive explosives that have to be handled at low temperatures in an atmosphere consisting of an inert gas.
Sesquioxides is an oxide containing three atoms of oxygen with two atoms of another element. For example aluminium oxide is sesquioxide having formula $$A{l}_2{O}_3$$. Many sesquioxides contain the metal in the +3 oxidation state.
Now, moving on to the options one by one. According to the first two options, we need to know if they are colourless or not and paramagnetic or diamagnetic. Alkali metal ozonides are coloured and also paramagnetic. For example Lithium and sodium ozonide have red colour and Potassium and rubidium ozonide have dark red colour. Also, ozonides exhibit phenomena of paramagnetism due to unpaired p-electrons and because of these unpaired electrons they are coloured compounds.
Talking about the next two options, it is known that sesquioxides are paramagnetic in nature due to the presence of superoxide ions. Superoxide ions have one unpaired electron making it paramagnetic. Also, it is true that sesquioxides of alkali metal are peroxides superoxides.

Therefore, the correct statements are A, C and D.

Note:
Ozonide is an unstable and reactive polyatomic anion ${O_3}^{-}$ analog of ozone. Alkali metal ozonides are colourless and paramagnetic in nature. Sesquioxides is an oxide containing three atoms of oxygen and two atoms of another element. They are paramagnetic due to the presence of superoxide. Sesquioxides of alkali metal are peroxides superoxides.