Question

Is \[HF\] a strong acid?

Answer 1

Hint: Acids are chemical substances that can dissociate freely in the presence of water and release a proton \[\left( {{H^ + }} \right)\] . A strong acid can easily completely dissociate into ions, and a weak acid cannot be easily completely dissociated into ions.

Complete answer:
Chemical compounds are classified into three types based on the nature of those compounds.
They are acids, bases and neutral compounds.
An acid is a chemical substance that can release a proton \[\left( {{H^ + }} \right)\] or it can accept a hydroxide ion. Some of the examples were hydrochloric acid and boric acid.
A base is a chemical compound that can abstract a proton or donate a hydroxide ion. Some of the examples were potassium hydroxide and sodium hydroxide.
Neutral compounds give both proton \[\left( {{H^ + }} \right)\] and hydroxide ion \[\left( {O{H^ - }} \right)\] , and are neutral in nature. The best example for a neutral compound is water.
Hydrofluoric acid has the molecular formula \[HF\] .
It contains one hydrogen atom and one fluorine atom.
Though it contains one hydrogen atom it cannot be considered as a strong acid.
The dissociation of \[HF\] will be as follows:
\[HF + {H_2}O \rightleftharpoons {H_3}{O^ + } + {F^ - }\]
Hydrofluoric acid \[\left( {HF} \right)\] contains a fluorine atom which is smaller in size, and the electronegativity differences of hydrogen and fluorine are large, but the bond is of very short length, makes the atoms tightly bound to each other. Thus, Hydrofluoric acid \[\left( {HF} \right)\] is not a strong acid.

Note:
The electronegativity difference makes the compound to be acidic and polar, but the small size of fluorine atom leads to greater nuclear attraction on the hydrogen atom, makes the bond shorter and very difficult to break the bond, thus Hydrofluoric acid \[\left( {HF} \right)\] is a weak acid.