The importance of water as a b
Water is the most available compound on earth and is essential to life itself, without water, Earth would not exist. Water is a major component of cells, typically forming between 70 and 95% of the mass of the cell. This means that we are made approximately 80% water by mass, with some soft bodied creature, such as the jellyfish, are made of up to 96% of water. Water is the up-most important compound covering 75% of Earth, where it provides an environment for organisms to live in.Water itself is a simple molecule made up of 2 hydrogen atoms and one oxygen atom, H2O. The hydrogen and oxygen atoms are bonded covalently via a shared pair of electrons. Thus there are 4 pairs of electrons surrounding the oxygen atom, two pairs involved in covalent bonds with hydrogen, and unshared pairs on the opposite side of the oxygen atom. Oxygen is an electronegative atom compared with hydrogen. Covalent bonds are formed by sharing electrons in the outer shelves of the quantum shells, however in the case of water the large number of protons in the oxygen nucleus have a stronger attraction for these shared electrons than the comparatively tiny hydrogen nuclei. As a result pulling the electrons slig
It requires 300 J per gram of ice to melt it to water. This provides support for soft-bodied creatures such as worms, slugs and jellyfish, which therefore do not require a supporting skeletal system. This is because of the hydrogen bonds that hold the water molecules in a liquid state. Water has a boiling point of 100"aC and a melting point of 0"aC, this is unusual for a molecule of its size because other molecules of a similar size such as CO2 are gaseous at room temperature whereas water is a liquid. An electrostatic attraction between the partial positive charges of the hydrogen atoms and the slight negative charge of the oxygen results in the formation of a weak hydrogen bond as shown in the above illustration. Thermal PropertiesWater also has many thermal properties as a temperature stabiliser. This means that the layer of ice insulates the water below, which stays at 4"aC and aquatic life can continue!Water and Chemical Reactions Water is a medium for many reactions, especially those that occur in cells. Water also has a High Latent Heat of Fusion from solid to liquid. Animals use this property of water by using excess body heat to evaporate water from their surfaces, resulting in them transferring a lot of energy into the environment but only losing a little water. Water also has a High Specific Heat Capacity, the result of this is that it takes 4. This means that it takes a lot of heat energy to raise the temperature of water significantly, but once warm it cools slowly. Without water these two essential reactions would not occurs and life would not be able to continue on Earth. The cohesive properties of water allows plants to pull up water through xylem vessels from the roots to the leaves, this is called transpiration stream. Sweating and panting are based on this principle.
Common topics in this essay:
Polarity Water,
Surface Tension,
Properties Water,
Heat Capacity,
Reactions Water,
Water's Density,
,
Earth Transparency,
Heat Fusion,
Vaporisation Animals,
water molecules,
hydrogen bonds,
oxygen atom,
hydrogen atoms,
cohesive properties,
properties water,
water thermal properties,
tension creatures,
surface water,
thermal properties,
gram water,
partial positive charges,
temperature stabiliser water,
cohesive properties water,
hydrogen bonds water,
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