Identify the correct order of solubility in aqueous medium

Ce³⁺, La³⁺, Pm³⁺ and Yb³⁺ have ionic radii in the increasing order as

The atomic numbers of vanadium (V), chromium (Cr), manganese (Mn) and iron (Fe) are respectively 23,24,25 and 26. Which one of these may be expected to have the highest second ionisation enthalpy?

Which one of the following is correct order of increase of size ?

An extra electron is added at the periphery of nitrogen atom in the formation of anion. What will be the ratio of effective nuclear charge of nitrogen atom and nitrogen anion?

Which element was named as Eka-silicon in Mendeleev's classification of elements ?

Based on lattice energy and other considerations which one of the following alkali metal chlorides is expected to have the highest melting point?

In which of the following pairs does one elements exist as a solid and the other as a liquid under normal conditions ?

Which one of the following is smallest in size ?

The charge/size ratio of a cation determines its polarising power. Which one of the following sequences represents the increasing order of the polarising power of the cationic species, K⁺, Ca²⁺, Mg²⁺, Be²⁺?