The reason for the stability of the $Gd^{3+}$ ion is.....

Which element from the following is the last element of the $5d$-transition series?

The liquefied metal which expands on solidification is

The correct statement$(s)$ about $Cr^{2+}$ and $Mn^{3+}$ is(are)
[Atomic numbers of $Cr = 24$ and $Mn = 25$]
$(A)$ $Cr^{2+}$ is a reducing agent
$(B)$ $Mn^{3+}$ is an oxidizing agent
$(C)$ Both $Cr^{2+}$ and $Mn^{3+}$ exhibit $d^4$ electronic configuration
$(D)$ When $Cr^{2+}$ is used as a reducing agent,the chromium ion attains $d^3$ electronic configuration

Which of the following ions has the least magnetic moment?

Which property from the following is $NOT$ exhibited by interstitial compounds?