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Acidic and basic solutions


Dilution of acids and bases


1) What is a dilution ?

Dilution simply consists in adding water in an aqueous solution.
It makes increase the proportion of solvent compared to that of the solutes.


2) Precautions for diluting

When a solution of acid or base is mixed with water some precautions must be taken:
- Protective gloves should be worn.

- It is better to add the acid solution in water and not the opposite because the water in contact with a large amount of acid can cause temperature rises more or less violent which projects some acid droplets.
This precaution especially concerns highly acidic solutions

3) Effects of dilution on pH

If we dilute an acidic solution:
- The solution becomes less acidic.
- Its pH increases and approaches 7.

If we dilute a basic solution:
- The solution becomes less basic.
- Its pH decreases and approaches 7


Comment: The dilution of an acidic solution increases its pH but it can not become greater than 7 because the added water is not basic.
Conversely the dilution of a basic solution decreases its pH, but it can not be less than 7 because the added water is not acidic





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