Question

Differentiate between strong and weak acids. Identify the strong and weak acids from the following list of acids:
-Hydrochloric acid.
-Acetic acid.
-Formic acid.
-Nitric acid.

Answer 1

We know that acids are chemical substances that donate hydrogen ions or protons when mixed in solution. An acid is any hydrogen-containing substance that is capable of donating a proton (hydrogen ion) to another substance. A base is a molecule or ion able to accept a hydrogen ion from an acid. Acidic substances are usually identified by their sour taste.

Complete step by step solution:
Acids are classified into strong acid and weak acid on the basis of their degree of dissociation, also known as $\alpha$ . Degree of dissociation refers to the amount of solute dissociated into ions. This shows the hydrogen chloride dissolved in the water splitting to give hydrogen ions in solution and chloride ions in solution. Now let us discuss what a weak acid really is.
By contrast, a weak acid is one which doesn't ionize fully when it is dissolved in water. Ethanoic acid is a typical weak acid. It reacts with water to produce hydronium ions and ethanoate ions, but the back reaction is more successful than the forward one.
At any one time, only about $1$ of the ethanoic acid molecules have been converted into ions. The rest remain as simple ethanoic acid molecules. Therefore, from the above analysis and explanation we can conclude that strong acids are those whose degree of ionization is more than $30$ and whose solutions contain more ions than molecules. Weak acids are those whose degree of ionization is less than $30$ . All organic acids are weak acids. Hydrochloric acid and Nitric acid-strong as their degree of ionization is more than $97$ Acetic and formic acids-weak as they are organic acid.

Note:
Remember that please be as clear as possible with the concept of ionization in water of different compounds as the knowledge of this concept is essential for you to be able to solve this question easily. A strong acid is one which is virtually $100$ ionized in solution and splits into aqueous versions of its constituent cation and anion. Some common strong acids include sulphuric acid, hydrochloric acid and nitric acid.