Which of the following alkaline earth metals shows some properties similar to aluminium?

$A$ chemistry student wants to identify the metal ion in a salt. They make a paste of the salt with concentrated $HCl$ on a clean platinum wire loop. If they take a small amount of this paste and place it in a non-luminous flame,it produces a green flame. Which metal is present?

Which of the following statements is not correct?

Which metal has $2$ electrons in the outermost orbit?

Match the compounds in List-$I$ with their chemical formulas in List-$II$ and select the correct answer using the codes given below:
List-$I$ (Compounds) | List-$II$ (Formulas)
$(A)$ Plaster of Paris | $(i) \, CaSO_4 \cdot 2H_2O$
$(B)$ Epsomite | $(ii) \, CaSO_4 \cdot \frac{1}{2} H_2O$
$(C)$ Kieserite | $(iii) \, MgSO_4 \cdot 7H_2O$
$(D)$ Gypsum | $(iv) \, MgSO_4 \cdot H_2O$

In which of the following is the hydration energy higher than the lattice energy?