Question

Choose the correct option relevant to $NaOH$ , $NaOH$ is a ?
A.Strong acid
B.Strong base
C.Weak acid
D.Weak base

Answer 1

The criteria to decide whether a given substance is an acid or base is determined using different laws. There are three laws that define whether a substance is acidic or a base using a slightly different concept. but all the concepts provide the correct details with slightly different approaches.

Complete answer: To answer this question, we will dig into the laws describing the acid and base. For this question we will use the Arrhenius principle of acid and base.
So, according to the Arrhenius acid – base theory , an acid is a chemical species that gives hydrogen ions or the hydronium ions in the water. And according to his concept Arrhenius base is a chemical species that gives hydroxide ions in the water.
So, by considering the definition of the Arrhenius acid and base , the strong base is the chemical species which dissociates completely in the water to give hydroxide ions.
For the sodium hydroxide , $NaOH$ :
Let’s look into its dissociation reaction in the water:
$NaOH \to N{a^ + } + O{H^ - }$
So, as we can see that sodium hydroxide dissociates completely in the water and produces hydroxide ions , $O{H^ - }$ in the water , so it is a strong base.
Therefore, the correct answer is option (B).

Note:
In addition to the Arrhenius concept of acid and base , there is also a concept of Bronsted and Lowry . According to the Bronsted and Lowry concept of acid and bases , an acid is a chemical species that donates the hydrogen ions and the bronsted base is the chemical species that accepts the hydrogen ions.