Amongest following the lowest degree of paramagnetism per mole of the compound at $298 K$  will be shown by

Cuprous ion is colourless while cupric ion is coloured because

The ${E^\Theta }\,\left( {{M^{2 + }}/M} \right)$ value for copper is positive $(+0.34 \,V ) .$ What is possible reason for this? (Hint: consider its high $\Delta_{ a } H^{\theta}$ and low $\Delta_{ hyd } H^{\theta}$ )

Among $\mathrm{VO}_2^{+}, \mathrm{MnO}_4^{-}$and $\mathrm{Cr}_2 \mathrm{O}_7^{2-}$, the spin-only magnetic moment value of the species with least oxidising ability is...................$BM$ (Nearest integer).

(Given atomic member $\mathrm{V}=23, \mathrm{Mn}=25, \mathrm{Cr}=24$ )

Which of the following pair will have effective magnetic moment equal

Amongst $TiF_6^{2 - },CoF_6^{3 - },C{u_2}C{l_2}$ and $NiCl_4^{2 - }$ (Atomic number $Ti = 22,$ $Co = 27,$ $Cu = 29,$ $Ni = 28$). The colourless species are