Arrange the following ions in the increasing order of their magnetic moments: $(i) \, V^{4+}$,$(ii) \, Mn^{4+}$,$(iii) \, Fe^{3+}$,$(iv) \, Ni^{2+}$. $[V = 23, Mn = 25, Fe = 26, Ni = 28]$

Gadolinium (atomic number $= 64$) is a member of the $4f$ series. Its electronic configuration in the $+3$ oxidation state is $[Xe] 4f^7$. What is the ground state electronic configuration of gadolinium?

Consider $|x|$ as the difference in oxidation states of Mn in the highest manganese fluoride and the highest manganese oxide. The ions with $|x|$ number of unpaired electrons from the following are: $A$. $Sc^{3+}$ $B$. $Zn^{2+}$ $C$. $V^{2+}$ $D$. $Fe^{2+}$ $E$. $Co^{2+}$ Choose the correct answer from the options given below:

The $3d$ elements show variable oxidation states because the energies of the following sets of orbitals are almost similar:

Which of the following is a soft metal?

Which of the following pairs has the same size?