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Acidic and basic solutions

Chemical reaction between iron and hydrochloric acid

The purpose is to study the chemical reaction between iron and hydrochloric acid.

We use:
- Iron powder (Iron powder is more reactive than compact iron )
- A hydrochloric acid solution.
- A test tube which allows a better observation.

Reaction between iron and hydrochloric acid:
reaction between iron and hydrochloric acid

We observe the formation of bubbles which indicate that a gas forms
To understand this chemical reaction we must identify the gaz, and analyze the composition of the aqueous solution in order to check a possible change.

Analysis of the gas:
The test for hydrogen gas is positive. This reaction therefore produces dihydrogen.

Analysis of the resulting solution:
- A measurement of pH shows that the latter increased: the solution is less acidic, hydrogen ions therefore have been consumed.
- The addition of silver nitrate leads to the formation of a white precipitate which indicates that the chloride ions are still in solution.
- The test for iron 
(II) ions is positive: Iron (II) ions (Fe 2+) have formed.

- The reactants are substances initially gathered: iron and hydrochloric acid.
- Products are substances that have formed: dihydrogen and iron (II) ions that form with chloride ions a solution of Iron(II) chloride

Simple word equation:

                                    iron + hydrochloric acid →  dihydrogen + Iron(II) chloride                            

Science class

Mechanics lessons

Water on Earth
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Properties of water in different states

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The conductivity of aqueous solutions
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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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