Question

What are the properties of acid?
A) That is capable of donating \[{H^ + }\]
B) That has lower pH
C) \[HCl\] is an acid
D) All of the above

Answer 1

Hint: We must have to remember that it is easy to identify a base and an acid. As we know, a base usually contains a hydroxide ion and an acid contains \[{H^ + }\] ion. Acid can turn blue litmus red and it is sour in taste.

Complete answer:
Option A) this option can be correct as acid is an ion or molecule which is capable of donating a proton. These proton donors form Hydronium ions and are known as Arrhenius acid.
We need to remember that according to Arrhenius concept, an acid when dissolved in water releases \[{H^ + }\] since when an Arrhenius acid releases \[{H^ + }\], \[{H_2}O\] molecule accept it forming Hydronium ion(\[{H_3}{O^ + }\])
\[{H_2}O + {H^ + } \to {H_3}{O^ + }\]
Option B) This option can be correct as acid has lower \[pH\]. The value of \[pH\] in acid is below $7$, as \[pH\] =7 is neutral and \[pH\] above 7 is a base.
Option C) this option can be correct as \[HCl\] is an acid.
\[HCl\]is a strong acid which can also be known as Arrhenius acid.
On making an aqueous solution of\[HCl\], it dissociates itself into \[{H^ + }\] and \[C{l^ - }\] ions.
\[HCl \to {H^ + } + C{l^ - }\]
We need to know that as the concentration of \[{H^ + }\] increases in the solution, thus \[HCl\]is an Arrhenius acid.
Option D) this option is correct as all the options given above are correct.

Note:
Sometimes, when an Arrhenius base reacts with an Arrhenius acid the products so formed are water and a salt, this type of reaction may be called as Neutralization reaction. Also, Arrhenius theory is limited to acid-base chemistry only.