PHYSICAL, CHEMICAL AND BIOLOGICAL PROPERTIES OF WATER NEED FOR DRINKING

ASSIGNMENT ON

ROCK WATER INTERACTION

(GEOL/3/OE/22)

PHYSICAL, CHEMICAL AND BIOLOGICAL PROPERTIES OF WATER NEED FOR DRINKING

SUBMITTED BY

LALTANPUIA

GOEG/12/206

All living things, from the smallest insect need water to live. Experts predict that by 2025, 1/3 of the world’s population will not have water due to the increase in population and water contamination. Each person discharged about 200,000,000,000 coliforms per day. Coliform bacteria are therefore very numerous-and the most common ad widespread health risk associated with drinking water is microbial contamination, the consequences of which mean that its control must always be of paramount importance. Earth currently has estimated 6.9 billion populations as of July 1, 2011 by the United States census bureau.

The uses of water:

Our world is a planet that is dominated by water and through the years the development in the study of water has been improved and practically tested. There are a lot of uses of water and the following are just a few of its examples.

1. The water is one of the most important sources of a human life.

2. Water is the habitat of several species.

3. Water serves as our main course for the human hygiene.

4. Water is the base of all drinks and beverages. Etc.

THE WATER AND ITS PROPERTIES: THE PHYSICAL, CHEMICAL AND BIOLOGICAL PROPERTIES OF WATER

PHYSICAL PROPERTIES:

Water has several other unique physical properties. These properties are:

1. Water has a high specific heat. Specific heat is the amount of energy required to change the temperature of a substance. Because water has a high specific heat, it can absorb large amounts of heat energy before it begins to get hot.

2. Water in a pure state has a neutral pH. As a result, pure water is neither acidic nor basic. Water changes its pH when substances are dissolved in it.

3. Water conducts heat more easily than any liquid except mercury. This fact causes large bodies of liquid water like lakes and oceans to have essentially a uniform vertical temperature profile.

4. Water molecules exist in liquid form over an important range of temperature from 0 - 100° Celsius. This range allows water molecules to exist as a liquid in most places on our planet.

5. Water is a universal solvent.

6. Water has a high surface tension. In other words, water is adhesive and elastic, and tends to aggregate in drops rather than spread out over a surface as a thin film. This phenomenon also causes water to stick to the sides of vertical structures despite gravity’s downward pull.

CHEMICAL PROPERTIES:

Water’s chemical formula is H2O. The water molecule is odd shape with both hydrogen atoms occurring on the same side of the oxygen atom gives water its ability to “stick” to itself and to other surfaces. The hydrogen atoms create a positive electrical charge while the oxygen atom creates a negative charge. The attraction to one another is what causes water to form droplets. The chemical properties make water essential to the functioning of living things including human beings. We must ingest or drink water in order to maintain good health.

   This model of a water molecule shows the arrangement of one oxygen atom bound to two atoms of hydrogen and their positive and negative charges. Arranged water molecules positive to negative charges make water “sticky” and form drops or beads on a smooth surface. Water beads on hood of a car are because of the arrangement of water molecules.

Some chemical properties of water are:

1. ph

2. Alkalinity

3. Total hardness

4. Iron, manganese,

5. metal-zinc, copper, chromium, lead

6. Nitrate/nitrite

7. Arsenic, fluoride

8. Chloride

9. Total and free chlorine

BIOLOGICAL PROPERTIES:

1. Adhesion: water tends to stick unlike substances. Example is water sticking to blood vessels.

2. Cohesion: Which water molecule clings together due to Hydrogen bonding; the surface film (top layer of water) is held by surface tension. Example is spilled water forming a puddle.

3. Solvency:  Water is considered a universal solvent for its ability to dissolve a wide range of substance since it is a polar molecule. Example is salt or sugar dissolving in water.

4. Chemical reactivity: water can participate in chemical reactions. Example: involvement of water molecules in dehydration synthesis and hydrolysis.

5. Thermal stability: water has a high heat capacity, so it requires a lot of energy to heat up; requires 1 cal to raise 1 gram of water by 1 degree Celsius. Example: stability of the oceans temperature during summer and winter.