1. Water and it’s Properties

6. Physical Properties

7. PURE WATER
• is an odorless and tasteless
liquid
• Bluish tint
• At standard atmospheric
pressure, its freezing point is
0°C and boiling point is 100°C

8. Density is a measure of mass per volume.
The average density of an object equals its
total mass divided by its total volume.

9. Water is at its maximum
density at a temperature
of 4°C. It has the unusual
property of contracting in
volume as it is cold to
4°C, and then expanding
when cold from 4°C to
0°C.
The only liquid that
expands when it freezes.
This makes the density of
ice lower than that of
liquid water and that is
why ice floats on water.

10. The boiling point is the temperature at which the vapor
pressure of a liquid equals the external pressure
surrounding the liquid.

11. Water has a relatively high boiling
point at 100 °C.
However, the boiling point of water
depends on the atmospheric pressure,
which changes according to elevation.
Water boils at a lower temperature as
you gain altitude (e.g., going higher
on a mountain), and boils at a higher
temperature if you increase
atmospheric pressure (coming back
down to sea level or going below it).

12. The boiling point of water also
depends on the purity of the water.
Water that contains impurities (such
as salted water) boils at a higher
temperature than pure water.This
phenomenon is called boiling point
elevation.

13. Specific heat of a substance is the ratio of the amount
of heat required to change its temperature to cause the
same temperature change in the same mass of water.

14. Water takes much longer time
to heat up and also to cool
down .
Water temperature fluctuates less
than land temperature such that
land temperature, like the oceans,
serve as moderating influence on
the earth’s climate.

15. The ability of a liquid (solvent) to dissolve solids (solute)

16. Water as the “Universal Solvent”
Water is the most commonly used polar solvent making
it the most effective liquid for transporting dissolved
nutrients, and eliminating toxic wastes in the body

17. Water as the “Universal Solvent”
The most important agent in the erosion of
weathered materials on earth’s surface

18. Water as the “Universal Solvent”
This ability makes the water easily and stays polluted

19. The elastic tendency of a fluid surface which makes it
acquire the least surface area possible.

20. This property is caused
by the molecules in the
liquid being attracted to
each other (cohesion).

21. The surface can hold up
a weight, and the
surface of a water
droplet holds the droplet
together, in a ball shape.

22. Surface tension allows
insects (e.g.Water
Strider), usually denser
than water, to float and
slide on a water surface.