Question

Why is mercury liquid at room temperature?
A. They have a boiling point
B. They have high intermolecular forces
C. Valence electrons are not shared easily
D. None of the above

Answer 1

Hint: We know that mercury is a metal which exists in a liquid state. Its atomic number is 89 and the chemical formula is Hg. It can be changed to solid at a temperature of $-{38.85}^{\circ }\mathrm{C}$. It is also a very good conductor of electricity. It is only one metal that exists in liquid state.

Complete step by step answer: We know that type of bonding between the atoms determines the physical states of elements. If the bonding is very strong, the element exists in a solid state and if the bonding is weak then the element exists in a liquid state.
       Let’s come to Mercury. Mercury possesses a unique electronic configuration, that is,
$\left[\mathrm{X}\mathrm{e}\right]4f^{14}5d^{10}6s^2$ . According to this configuration of mercury, we see that all the subshells are completely filled due to which it resists the removal of an electron. This makes mercury similar to noble gas elements. Therefore, mercury forms a very weak bond and exists as liquid in room temperature. Hence, option C is the correct answer.

Additional Information: Now, we discuss some of the chemical properties of mercury. It generally does not react with acids, but oxidizing acids (nitric acid and sulphuric acid) undergoes reaction with it to result in nitrate, sulphate and chloride salts. Mercury forms amalgam with zinc, gold and many other metals.

Note: Mercury is a poor conductor of heat but it is used in thermometers due to its high coefficient of expansion. This property helps to note the slightest change of temperature. Also because of its high boiling point, measurement of very high temperature is possible.