In Chemistry, the most important essential concepts is to understand the chemical definition of a term. This will allow you answer tricky exam-based questions with less stress, as you can draw upon your knowledge on “definition” which will not be incorrect.

An acid is a compound, which produces hydrogen ions (H+) as the only +ve ions when dissolved in water.

When HCl (a covalent molecule) is bubbled into water, it “dissolves” to form H+ ions & Cl- ions known as Dissociation or Ionisation.

We say HCl dissociates into H+ ions & Cl- ions when dissolved in water
HCl(aq) –> H+(aq) + Cl-(aq)

Acids only have Acidic properties when they are dissolved in water.
If water is absent, an acid does NOT show its acidic properties.

All acids contain hydrogen atom but not all substances that contain hydrogen are acids.
E.g. Ammonia & Methane are not acids even they contain Hydrogen atoms in their chemical formulae

Let’s check out a question to see if you understand.

Quick Check 1:
Which of the following ions is not present in aqueous sulphuric acid?
A. H +
B. OH -
C. SO3 2-
D. SO4 2-

PS: Do leave your suggested answers in the “Comments Section” directly below this post.

PPS: This post belongs to a series of blogposts that is associated with Secrets of “Acids, Bases & Salts and Qualitative Analysis revelaed”

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