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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

Science class

Mechanics lessons

Water on Earth
Changes of state in the nature: the water cycle
Water in human body
Test for water
Properties of water in different states

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States of matter and its changes
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Heterogeneous mixtures
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Dissolving a solid in water
Conservation of mass on dissolving
Miscibility in water

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Mass of a liter of water
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Most common metals
How to distinguish metals ?

Corrosion of metals
Electrical conductivity of solid materials
Electrons and free electrons
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The conductivity of aqueous solutions
Aqueous solutions and ions
The direction of movement of ions
Formation of ions
Tests for ions

Acidic and basic solutions

pH of aqueous solutions
Ions in acidic and basic solutions
Dilution of acids and bases
Composition of hydrochloric acid
Chemical reaction between iron and hydrochloric acid

Electrochemical cells and chemical energy

Chemical reaction beteween a copper sulphate solution and zinc
Copper sulfate and zinc battery
Basics of electrochemical cell


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