HF is less polar than HBr

absolutely pure water does not contain any ions

chemical bond formation takes place when forces of attraction overcome the forces of repulsion

in covalency transference of electron takes place

$$O_2^-$$ < O₂ < $$O_2^+$$ < $$O_2^{2-}$$

$$O_2^{2-}$$ < $$O_2^-$$ < $$O_2$$ < $$O_2^{+}$$

$$O_2^-$$ < $$O_2^{2-}$$ < $$O_2$$ < $$O_2^{+}$$

$$O_2^{+}$$ < $$O_2$$ < $$O_2^-$$ < $$O_2^{2-}$$