Question

Both zinc and mercury belong to the same group in which differentiating electron enters into d - sub shell of the penultimate shell. But zinc is a solid while mercury is a liquid. How do you justify this?

Answer 1

1.Zinc belongs to the 4th period and 3d series of transition metals and also has electronic configuration as$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}$and Mercury has $\left[Xe\right]4f^{15}5d^{10}6s^2$.Both Zn and Hg have valence electrons in the penultimate shell(d-sub shell) and belong to the same group.

2.Zinc can contribute 2 electrons to form metallic bond.Thus, strong metallic bind in zinc imparts hardness to the metal which makes its physical state to be solid.

3. Mercury belongs to 6th period and 5d series of transition metal with electronic configuration $\left[Xe\right]4f^{15}5d^{10}6s^2$.Due to the poor screen effect of 14 f electronic, the effective nuclear force of attraction on the outermost shell increases.

4. Therefore, covalent bond exists in Hg which is held by weak attractive forces and hence it exists as liquid.

Hence, Zn is a solid and Hg is a liquid.