Notes
Water
A water molecule:
e
Each H shares a pair of electrons with the oxygen. The oxygen
8- ft has a greater af finity for electrons than the H’s so it pulls the
µ
'
electrons closer.
i
This makes the O slightly negative and the H slightly positive.
: This creates dif ferently charged regions making water a
ft H
polar molecule. Because it has two charged regions it’s
dipolar.
The slight negative charge on the oxygen atom makes it attract the slightly positive hydrogen atom of
: another water molecule. These attractions are called hydrogen bonds.
Many of water‘s properties are due to the ability to form hydrogen bonds.
Water is a dipole; its excellent at dissolving ions and other polar substances. Positive sodium ions attract
: to the negative on oxygen. Negative chlorine ions attract the positive on hydrogens.
Nonpolar molecules like fats are insoluble in water because they have no charge therefore no attraction.
Water is a liquid at room temperature; it provides a liquid environment for reactions within cells and a
: living environment for aquatic species.
Water has a high specific heat capacity. Water resist temperature change which provides a thermally
stable environment for life.
Water has high latent heat of vaporisation. This means when water evaporates from an organism
: through sweating or transpiration it requires a lot of energy and it provides a significant cooling af fect.
Water has high latent heat of fusion. Water inside cells and in aquatic habitats are slow to freeze there for
providing thermally stable environment for life.
Water has a density anomaly. The solid is less dense than liquid which is an anomaly. When water freezes
:
each molecule forms hydrogen bonds with four others. This creates a lattice that holds the molecules
farther apart than liquid water so ice floats on the water this allows aquatic organisms survive under
the ice on frozen lakes and ponds.
Water forms hydrogen bonds with adjacent water molecules but not with molecules in the air this leads
to surface tension and this leads to skin on the water. This is perfect habitat for animals such as pond
skaters and water boatmen..
Water
A water molecule:
e
Each H shares a pair of electrons with the oxygen. The oxygen
8- ft has a greater af finity for electrons than the H’s so it pulls the
µ
'
electrons closer.
i
This makes the O slightly negative and the H slightly positive.
: This creates dif ferently charged regions making water a
ft H
polar molecule. Because it has two charged regions it’s
dipolar.
The slight negative charge on the oxygen atom makes it attract the slightly positive hydrogen atom of
: another water molecule. These attractions are called hydrogen bonds.
Many of water‘s properties are due to the ability to form hydrogen bonds.
Water is a dipole; its excellent at dissolving ions and other polar substances. Positive sodium ions attract
: to the negative on oxygen. Negative chlorine ions attract the positive on hydrogens.
Nonpolar molecules like fats are insoluble in water because they have no charge therefore no attraction.
Water is a liquid at room temperature; it provides a liquid environment for reactions within cells and a
: living environment for aquatic species.
Water has a high specific heat capacity. Water resist temperature change which provides a thermally
stable environment for life.
Water has high latent heat of vaporisation. This means when water evaporates from an organism
: through sweating or transpiration it requires a lot of energy and it provides a significant cooling af fect.
Water has high latent heat of fusion. Water inside cells and in aquatic habitats are slow to freeze there for
providing thermally stable environment for life.
Water has a density anomaly. The solid is less dense than liquid which is an anomaly. When water freezes
:
each molecule forms hydrogen bonds with four others. This creates a lattice that holds the molecules
farther apart than liquid water so ice floats on the water this allows aquatic organisms survive under
the ice on frozen lakes and ponds.
Water forms hydrogen bonds with adjacent water molecules but not with molecules in the air this leads
to surface tension and this leads to skin on the water. This is perfect habitat for animals such as pond
skaters and water boatmen..
