Answer:
A glance of earth taken from space will depict it blue. This blue colour is actually water, the major part of the earth is covered with water. We need water for almost everything, for example- drinking, bathing, cooking etc and therefore we should know about the properties of water. 65 % human body is composed of water. Water is essential for the survival of life on earth. Water is distributed unevenly on the earth’s surface. It forms a major solvent and dissolves almost every polar solute. So let us have a look at its properties.
Physical properties of water : Water is a colourless and tasteless liquid. The molecules of water have extensive hydrogen bonds resulting in unusual properties in the condensed form. This also leads to high melting and boiling points. As compared to other liquids, water has a higher specific heat, thermal conductivity, surface tension, dipole moment etc. These properties form the reason for its significance in the biosphere. Water is an excellent solvent and therefore it helps in the transportation of ions and molecules required for metabolism. It has a high latent heat of vaporization which helps in the regulation of body temperature
Chemical properties of water: Amphoteric nature:
Water can act as both acid and base, which means that it is amphoteric in nature.
Example:
Acidic Behaviour: H2O(l)+NH3(aq) ⇌ H3O+(aq)+NH+4(aq)
Basic Behavior: H2O(l)+H2S(aq) ⇌ H3O+(aq)+HS−(aq)
Redox reactions:
Electropositive elements reduce water to hydrogen molecule. Thus water is a great source of hydrogen. Let us see an example in this case:
2H2O(l)+2Na(s)→2NaOH(aq)+H2(g)
During the process of photosynthesis, water is oxidized to O2. As water can be oxidized and reduced, it is very useful in redox reactions.
Hydrolysis reaction
Water has a very strong hydrating tendency due to its dielectric constant. It dissolves many ionic compounds. Some covalent and ionic compounds can be hydrolyzed in water.
Explanation:
The answer would be C. Digestive
The <em />circulatory system <em>circulates</em> the blood and lymph throughout the body. The excretory system <em>excretes</em> the body wastes.
The answer is E; Self-interest study. This is due to the fact that the financier of the research, the beverage company, has vested interests in the research and will therefore be intuitively biased for the results to favour the sales of the beverage.
Yes it is and it only occurs in women.
Rinderpest disease is caused by a virus that affects hoofed animals, including cattle and wildebeest. In the 1950s, a cattle vaccination program was implemented to eradicate the disease in the Serengeti, and this led to dramatic changes in the populations of wildebeest and other species. The figure shows the number of wildebeest in the Serengeti ecosystem (shaded circles, left y-axis) and the prevalence (i.e., percentage) of individuals infected by rinderpest disease (unshaded squares and triangles, right y-axis) from 1958 to 2003.
