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Properties of water in different sates

The essential about water and its different states

The free surface of water

What is a free surface?
A liquid is in contact with its receptacle but also with air. The liquid surface in contact with air is also called " free surface ".

Diagram: free surface of water:

Free surface of water in a beaker

In a stationary vessel, the free surface of water is always flat and horizontal whatever the inclination of the vessel.

Diagram: free surface of water in an inclined beaker
Horizontal free surface of water in inclinated beakers

Properties of the liquids

Diagram: water in a beaker, an erlenmeyer and a measuring cylinder
Volume of water in a beaker, an erlenmeyer and a measuring cylinder

If liquid water is transferred into graduated containers of different shapes, it can be observed that water takes the same shape as its container but keeps the same volume.
Liquid water has its own volume but no own shape.

Properties of solids

If an ice cube is poured from one container to another it keeps its shape and its volume
Solid water has its own volume and its own shape.

Properties of gases

A gas enclosed in a container occupies all available space: it thus has no own shape.

If some air is enclosed in a plugged syringe its piston can be moved to reduce or to increase the volume of the air: air therefore has no own volume.

To sum up:

Own shape Own volume
Solid Yes Yes
Liquid No Yes
Gaz No No

The sand (like other substances composed of powder or grains) has properties that are close to those of liquids.
Each grain has a own shape and a own volume but the sand takes the shape its receptacle: it therefore has no own form (like a liquid).
However unlike liquids, its free surface isn't necessarily flat and horizontal.

Learn more about water and its properties

Basic properties of fluids and definition:

Properties of gases:

Properties of liquids, solids and gases explained for grade 4:

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

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
Volumetric mass density

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


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