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washing soda
Carbonate the juice

Washing soda. This name is given to hydrated sodium carbonate (Na2Co3. 10H20).
The name comes from the use of this salt to soften the water used in washing.


water(H₂O)
eau f

water . Water is hydrogen oxide

2H2 (gas) + O2 (gas) → 2H2O (liquid)

Water is one of the most common compounds on Earth. It is the most famous solvent, and all living organisms need it.

Water is a colorless liquid, and the following are some of its most important properties:

Freezing point 0°C
Boiling point 100°C
Density 1.0 g/cm3

(The maximum density of water is at 4°C) Unusually, water expands when it solidifies, which is why ice floats and water pipes burst when they freeze. Water does not conduct electricity, although it decomposes electrically if small amounts of acid (H2SO4) or alkaline (NaOH) are added to it. be a result
Hydrogen and oxygen release analysis:

2H2O (liquid) → 2H2 (gas) + O2 (gas)

There are two tests for the presence of water by changing the color of anhydrous salts.

2H2O (liquid) → 2H2 (gas) + O2 (gas)


CuSO4.(solid)+ 5H2O → CuSO4. 5H2O(solid)
Blue---white

Co Cl2 (solid) + 6H2O → CoCl2. 6H2O(solid)
Red---blue

These two tests indicate the presence of water, but they do not indicate whether it is pure. To determine the purity, the boiling point of the liquid can be taken.

Water is found in the atmosphere and in lakes, rivers, glades, seas and oceans. It is also found in rocks and living creatures. Water is constantly moving from one place to another on earth. See water cycle.

The most important chemical property of water is its use as a solvent. Water has polar bonds, which enables it to dissolve anionic solids such as sodium chloride (NaCl) as well as polar solids such as glucose (C6H12O6).

The water we drink is never pure. It always contains small amounts of gas (such as oxygen and carbon dioxide) and dissolved solids, some of which make the water hard, depending on the source of the water.
See hardness of water.


water cycle
cycle m de l'eau

W.C. Water is a constant movement around the Earth.
Whether in the oceans or in the air. Water falls to the ground in the form of rain, snow, hail, and sleet (a mixture of snow and rain), and freezes in the air in the form of frost and ice. Water falls in all its forms on the oceans, which are a widespread source of water, and it also falls on land, where it seeps into the ground and ultimately flows into lakes and rivers, whose waters end up in the seas and oceans. Evaporation occurs in these large areas of water, and the water returns and enters the atmosphere again. The cycle continues like this. Plants and animals take water from the ground for their own use, and this water can return to the atmosphere (through transpiration) or return to the ground. Large quantities of water are stored in the form of icebergs and in the polar ice caps.


water of crystallization
eau f de crystalisation

Crystallization water. Water chemically bound within crystals. Examples include:

CaSO4.2H2O
Na2CO3. 10H2O
CuSO4. 5H2O

Water can be removed by heating, which leaves behind an anhydrous salt. This can happen due to weak chemical bonds. Some salts containing water lose the crystallization of some of the chemically bound water upon exposure to air. This is called efflorescence.


weak acids and bases
Acids and bases are suitable

Weak acids and bases.
See strengths of acids and bases.