Essay on Water
April 30 2009
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Essay on Water
Published by admin at 3:58 am under Example Essays
Introduction
Water is an essential ingredient for the existence of life as we know it. Biochemical processes occur in aqueous environments, many of which use water. Water also plays a significant role in the process of photosynthesis ( 6 CO2 + 6H2O + 672kcal -> C6H12O6 + 6O2 ). Photosynthesis is the most basic and significant chemical reaction on earth, providing the primary nutrients, directly or indirectly, for all living organisms and is the primary source of atmospheric oxygen. Without water and its unique and unusual properties, life as we know it on earth would not exist. Water is the only substance naturally present on the earth that exists in three distinct states -solid, liquid, and gas. Many of the unique properties in the take for granted include the three physical phases, transparency, universal solvents, density behavior and temperature, high specific heat, high heat of vaporization, viscosity, surface tension and low compressibility. To understand why these properties exist in water and why they are essential to life on earth it is important to look at the shape and bonding patterns of the molecule because the uniqueness of water is a direct result of its shape and bonding patterns.
The shape of the water molecule
In the water molecule the oxygen atom is the central atom. It has four pairs of valence electrons surrounding it. Two of these pairs are shared which form the shared pairs form covalent bonds with the hydrogen atoms. The remaining two pairs are unshared and have a greater repulsive effect than the shared pairs. The combined repulsive effect of the two unshared electron pairs produces an H-O-H bond angle that is smaller than the H-C-H bond angle (109.47 degrees) in methane or the H-N-H bond angle (107 degrees) in ammonia. Actual measurement of the bond angle in water is 104.5. If the two hydrogen nuclei were
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Essay on Water
Published by admin at 3:58 am under Example Essays
Introduction
Water is an essential ingredient for the existence of life as we know it. Biochemical processes occur in aqueous environments, many of which use water. Water also plays a significant role in the process of photosynthesis ( 6 CO2 + 6H2O + 672kcal -> C6H12O6 + 6O2 ). Photosynthesis is the most basic and significant chemical reaction on earth, providing the primary nutrients, directly or indirectly, for all living organisms and is the primary source of atmospheric oxygen. Without water and its unique and unusual properties, life as we know it on earth would not exist. Water is the only substance naturally present on the earth that exists in three distinct states -solid, liquid, and gas. Many of the unique properties in the take for granted include the three physical phases, transparency, universal solvents, density behavior and temperature, high specific heat, high heat of vaporization, viscosity, surface tension and low compressibility. To understand why these properties exist in water and why they are essential to life on earth it is important to look at the shape and bonding patterns of the molecule because the uniqueness of water is a direct result of its shape and bonding patterns.
The shape of the water molecule
In the water molecule the oxygen atom is the central atom. It has four pairs of valence electrons surrounding it. Two of these pairs are shared which form the shared pairs form covalent bonds with the hydrogen atoms. The remaining two pairs are unshared and have a greater repulsive effect than the shared pairs. The combined repulsive effect of the two unshared electron pairs produces an H-O-H bond angle that is smaller than the H-C-H bond angle (109.47 degrees) in methane or the H-N-H bond angle (107 degrees) in ammonia. Actual measurement of the bond angle in water is 104.5. If the two hydrogen nuclei were