Common Misconceptions
3 min read

Acids, Bases And Salts

- Understand most confusing terms of the chapter in a very easy method
1

Acids can burn and eat away any material.

Acids hold a position of being dangerous.
Sure enough a drop of concentrated hydrochloric acid can damage any surface or burn your skin.
But there are many acids that are very gentle and are a part of various nutritious foods.
One such food stuff is Apple!
It contains malic acid- which pretty much does not cause any harm to us.
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Similarly vinegar is an acid, which is added to many cuisines and doesn't cause any harm to us.
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2

All acids release hydrogen ions and bases release hydroxyl ions.

If you are asked to name a few acids, are you more likely to say or ?
What if I add one more to your list- ? Are you going to erase it?
Contrary to what we are always told, there are many acidic substances which do not release in water.
Similarly, not all bases release ions. What do you think of ammonia? It may not contain a hydroxyl group, but it definitely produces a basic solution when it reacts with water.
This happens because ammonia accepts from water, leaving behind OH- ions in the solution - thus, making it basic.
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Here are some examples of acids and bases which may not fit in our traditional knowledge of acidic and basic substances:
Acids: ,,
Bases: ,,
3

A diluted form of acid is always that of a weak acid.

If we have an acid mixed with a lot of water or is diluted, we tend to think of it as a weak acid.
We naturally think dilute means weak and concentrated means strong.
But do you know that the underlying principles are different for the terms?
An acid is considered strong if it completely dissociates into its ions in water. But the same is not true for a weak acid - it does not undergo complete dissociation.
HCl and acetic acid are classic examples.
Hydrochloric acid completely breaks down into ions but not acetic acid.
Some of the acetic acid always remains in the undissociated form.
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What if we take the strong acid and mix it with water?It continues to break into its ions completely.
But with the addition of water, the volume of the solution increases. Remember that the amount of acid (or the ions in the dissociated form) does not change here.
This leads to a decrease in the amount of ions per unit volume of the solution - making the solution dilute.
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In the case of little or no water, the volume of the solution would be much lower. This would mean higher amount of the ions per unit volume of the solution- making it more concentrated.
All in all, the terms Strong/weak basically refer to the extent of dissociation while the terms concentrated/dilute refer to the amount of ions per unit volume of the solution.
So, if we have HCl in the diluted form, it does not mean it is a weak acid. It's just that its concentration is reduced with the addition of water.