Question

Out of the following, which is the most stable compound?

• A. ${\left[Be\right(H_{2}O{)}_4]}^{2+}$
• B. ${\left[Mg\right(H_{2}O{)}_4]}^{2+}$
• C. ${\left[Ca\right(H_{2}O{)}_4]}^{2+}$
• D. ${\left[Sr\right(H_{2}O{)}_4]}^{2+}$

Answer 1

The correct option is A ${\left[Be\right(H_{2}O{)}_4]}^{2+}$

As we move down the group, polarization power decreases.
Also, $Be$ has incomplete octet so, it has highest tendecy to form complex and complete its octet.