Question

The strongest acid among the following is:
A.$NH_4^ +$
B.${H_3}{O^ + }$
C.$HF$
D.$N{H_3}$

Answer 1

This question gives knowledge about the acidic nature of chemical compounds. The acidic nature of chemical compounds helps in explaining the acidic character possessed by the compound. Acids are the chemical substances which react with other chemical compounds to donate hydronium ions.

Complete answer:
${H_3}{O^ + }$ is the strongest acid because it has the greater tendency to donate hydronium ions and the important characteristics of an acid is that they can donate hydrogen ion ions very easily whereas the important characteristics of bases is that they can donate hydroxide ions very easily.

Therefore, option $B$ is correct.

Note:
Acids are the chemical substances which react with other chemical compounds to donate hydronium ions. Acids generally possess low $pH$ values ranging between $0$ to $6$. When acidic compounds react with basic compounds, they lead to the formation of salts and water molecules. This type of reaction is known as neutralization reactions.
The acidic character of chemical compounds depends on various factors which are as follows:
$1$. The chemical compounds having cation with higher charge possess higher acidic character.
$2$. The chemical compounds having anion with smaller charge possess higher acidic character.
$3$. Higher the electronegativity, higher will be acidic character.
$4$. The higher ionization energy leads to higher acidic character.
$5$. Down the group, atomic size of the elements decreases which leads to smaller size of cations. So, acidic character also decreases.