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Free online chemistry lesson for elementary school, middle school and high school.
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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
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
Vaporization of water
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

Air and atmosphere
Earth's atmosphere protect us
Threats to the Earth's atmosphere
Composition of air
Air and life
Atoms and molecules
Molecules in mixtures and pure substances
Molecules and states of matter
Composition of molecules
Constituents of the atoms
The electrical neutrality of the atom

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

Most common metals

How to distinguish metals ?

Corrosion of metals

Electrical conductivity of solid materials

Electrons and free electrons

Electric current in metals
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


Mass and volume

Measuring volume with a graduated cylinder

1) Which container can be used to measure volume ?
A water volume can be measured with a graduated container as a beaker, flask, or conical measure.

Graduated containers

However, their indications of volume are approximations and for a higher accuracy a graduated cylinder is more suitable.

Graduated cylinder

2) Method for using a graduated cylinder

Step 1:
There are some graduated cylinders of various capacities (5 mL to 500 mL in general), each with its own system of graduation.
Therefore, the volume corresponding to each division must first be determinate.

Graduated cylinders and their graduations

Step 2:
To measure volume, the graduation the closest  to the free surface of the liquid must first be determined.
The observer must then set his eyes at the same level as the free surface.

Observer identify graduation closest to free surfac

Step 3:
Volume can be calculated using previous informations.

Measure of volume with graduated cylinders

Due to the capillary action, water tends to be attracted by the walls of its container. This phenomenon is negligible for wide containers but in narrow containers it can be observed that the surface becomes round (the surface is curved).
To correctly determine the volume of liquid then you should take as a reference the lowest point of the curved surface.

Graduated cylinder with curved surface