Which of the following salts is colourless?

Name a transition element which does not exhibit variable oxidation states.

The correct order of spin-only magnetic moment (in $BM$) for $Mn^{2+}$,$Cr^{2+}$,and $Ti^{2+}$ ions is:

Determine whether the following statements are True $(T)$ or False $(F)$:
$(a)$ Transition elements exhibit variable oxidation states.
$(b)$ The $E^o$ values for $Mn, Zn,$ and $Ni$ are more positive than expected from the general trend.
$(c)$ Any metal exhibits its maximum high oxidation state in oxide and chloride compounds.

Which of the following species is expected to show the highest magnetic moment? (At. Nos.: $Cr = 24$,$Mn = 25$,$Co = 27$,$Ni = 28$,$Cu = 29$)

The number of electrons in the outermost shell of the $3d-$ transition elements generally remains: