Assertion : H3PO4 and H2SO4 are known as polybasic acids.Reason : The...
Both A and R are true and R is the correct explanation of A.
Similarly bases which give two or more than two hydroxyl ions per molecule are known as polyacidic bases.
Assertion : H3PO4 and H2SO4 are known as polybasic acids.Reason : The...
Assertion: H3PO4 and H2SO4 are known as polybasic acids.
Reason: They have two or more than two protons per molecule of the acid.
The correct answer is option 'A': Both assertion (A) and reason (R) are true, and reason (R) is the correct explanation of assertion (A).
Explanation:
Polybasic acids are acids that contain more than one ionizable hydrogen atom per molecule. In other words, they can donate multiple protons (H+) when dissolved in water.
H3PO4 (phosphoric acid) and H2SO4 (sulfuric acid) are both examples of polybasic acids. Let's break down the reason given in the assertion:
1. H3PO4 (phosphoric acid):
- Phosphoric acid has three ionizable hydrogen atoms (protons) per molecule.
- In an aqueous solution, it can donate three protons (H+).
- The three ionizable hydrogens in H3PO4 are connected to three different oxygen atoms, making it a triprotic acid.
2. H2SO4 (sulfuric acid):
- Sulfuric acid has two ionizable hydrogen atoms (protons) per molecule.
- In an aqueous solution, it can donate two protons (H+).
- The two ionizable hydrogens in H2SO4 are connected to two different oxygen atoms, making it a diprotic acid.
Based on the above explanation, both the assertion and the reason are true. H3PO4 and H2SO4 are polybasic acids because they have more than two protons per molecule, which can be donated as H+ ions when dissolved in water.
Therefore, option 'A' is the correct answer.