Free energy, or Gibbs free energy (G), is the energy available to do work in a thermodynamic system at constant temperature and pressure. It determines the spontaneity of a reaction.
Europium (Eu) resembles Calcium (Ca) in the following ways:
(A). Both are diamagnetic
(B). Insolubility of their sulphates and carbonates in water
(C). Solubility of these metals in liquid NH3
(D). Insolubility of their dichlorides in strong HCI
Choose the correct answer from the options given below: