Question

Which elements normally exist in the liquid state?
(A) Iodine and mercury
(B) Mercury and chlorine
(C) Bromine and iodine
(D) Bromine and mercury

Answer 1

Hint: In given examples \[Cl,{\text{ }}Br,{\text{ }}I\]are halogens and mercury is metal. Halogens are non-metals generally found in either gaseous or liquid state and metals are found in solid state.

Complete step by step answer:
\[Cl,{\text{ }}Br,{\text{ }}I\]are halogens and they belong to the 17th group in the periodic table.
13th to 17th group elements in periodic table are non-metals. Generally, non-metals are either gaseous or liquid.
As we move down the group of periodic tables, the state of the element changes from gaseous to solid state.
Here, chlorine is gas, Bromine is liquid and Iodine exists in solid state.
Mercury belongs to the 12th group and 6th period of periodic table. It is only metal that exists in liquid state.
Mercury is a transition element. The liquid state of mercury can be explained on the basis of bonding present in d-orbitals.
The electronic configuration of mercury $[Hg]$ is,
$[$$]$$6{s^2}4{f^{14}}5{d^{10}}$d-orbital.
The d-orbitals have completely filled electrons therefore Hg does not form metallic bonds. So mercury is present in a liquid state.
Mercury is silver in color.
Bromine is thirst lightest halogen and is a fuming red brown liquid at room temperature. That evaporates easily to form similar colored gas. It’s electronic configuration is $Ar[3{d^{10}}4{s^2}4{p^5}].$
It is only non-metal that exists in a liquid state.

Therefore, from the above explanation the correct option is (D) Bromine and mercury.

Note:
Mercury is only metal and bromine is only non-metal that exists in liquid state.
Mercury is a transition element. Transition elements are those elements which are placed between metal and non-metals in a periodic table.
Bromine is halogen. In the word halogen “hal”-means “salt” and – “gen” means “to –produce”.