Chemistry

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Metals


Electrical conductivity of solid materials


Solid materials can be classified into two main categories:
- Electrical conductors that can be crossed by an electric current.
- Insulators that don't conduct electric current.


To determine whether a material is conductive, a test of conductivity can be performed using the following circuit:

Test of conductivity on solid materials


The principle of this test is simple:
- If the bulb lights, it indicates that the electric current flows then the material is conductive.
- If the bulb doesn't light, it indicates the electric current doesn't flow so the material is insulative.


Test results:

Tested materias Test results:
Iron Conductor
Zinc Conductor
Aluminium Conductor
Copper Conductor
Copper sulfate powder Insulator
Salt powder Insulator
Wood Insulator
Plastic Insulator

This test permits to show that only metals are conductors and most other solid materials are insulators.
This characteristic can be explained by their microscopic properties





Science class

Mechanics lessons
Water

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

States of matter

States of matter and its changes
Boiling water
Water: freezing and melting
Changes of state: mass and volume
Molecules in different states of matter

Mixtures and solutions

Heterogeneous mixtures
Homogeneous mixtures
Decantation
Centrifugation
Filtration
Vaporization of water
Distillation
Chromatography
Dissolving a solid in water
Conservation of mass on dissolving
Miscibility in water

Mass and volume

Volume and its units
Measuring volume with a graduated cylinder
Mass and its units
Measuring the mass of a liquid
Mass of a liter of water
Volumetric mass density

Air and atmosphere

Atmosphere
Earth's atmosphere protect us
Threats to the Earth's atmosphere
Composition of air
Air and life
Pressure

Atoms and molecules

Molecules
Molecules in mixtures and pure substances
Molecules and states of matter
Atoms
Composition of molecules
Constituents of the atoms
The electrical neutrality of the atom

Combustions

Basics of combustion
The combustion of carbon
The combustion of butane

Atoms and chemical reactions

Chemical reactions
Chemical equations
Law of conservation of mass
Chemical synthesis

Metals

Most common metals
How to distinguish metals ?

Corrosion of metals
Electrical conductivity of solid materials
Electrons and free electrons
Electric current in metals

Ions

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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