Question

Which one is the liquid element: $Hg$ (or) $Zn$?
$
  A)Hg \\
  B)Zn \\
  C)Both\,A\,and\,B \\
  D)None\,of\,the\,above \\
$

Answer 1

Hint: We know that only two elements in the periodic table exist as liquid in room temperature. One of the elements belongs to group-17 and the other element belongs to group-12.

Complete step by step answer:
We know that there are two elements in the periodic table, which are seen as liquid states in the room temperature. Out of these elements, one of the elements belongs to group-17, which is a halogen family and another element is a member of group-12 that belongs to the zinc family.
The element in the halogen family that exists as liquid is bromine. Bromine belongs to the fourth period and it is a p-block element.
The element in the zinc family that exists as liquid is mercury. Mercury belongs to the sixth period and it is a d-block element.
We know that zinc also belongs to group-12 but it appears as a solid. Zinc belongs to the fourth period and it is a d-block element.
Bromine is liquid, non-metal, whereas mercury is a liquid and metal.
The melting point of bromine is ${\text{ - 7}}{\text{.}}{{\text{2}}^o}C$ and boiling point is ${58.8^ \circ }C.$
The melting point of mercury is ${\text{ - 38}}{\text{.}}{{\text{8}}^o}C$ and boiling point is ${356.7^ \circ }C.$
From the above explanation, we can observe that mercury is a liquid among the given options.
Hence, option A is the correct option.


Note:
The few other elements that exists in liquid state are,
-Gallium (metalloid)
-Rubidium (alkali metal)
-Caesium (alkali metal)
-Francium (alkali metal)
We have to know that all the above elements exist in liquid state slightly above the room temperature.