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acid rain
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The pH level of the water does have an effect on the growth of duckweed Introduction: Acid Rain- The acidity or the alkalinity of a substance is measured by using a pH scale. The pH scale is logarithmic (the –log [H+]). A substance that has a value of 1 – 6.99 is said to be acidic and a value of 7.1 – 14 means the substance is basic. The value of 7 means the substance is neutral. The pH of 5.6 is used as the baseline in identifying acid rain. At this pH level, carbon dioxide and distilled water are at equilibrium. Any precipitation that has a pH value of less then 5.6 is considered to be acid rain. Sulfur dioxide is one of the main causes of acid rain. This gas is emitted into the atmosphere thru natural sources such as volcanoes or thru the burning of fossil fuels. When sulfur dioxide reaches the atmosphere, it oxidizes and forms a sulfate ion. It then joins with hydrogen atoms and falls back down to earth. Nitric oxide and nitric dioxide are also components of acid rain. Acid rain has a great impact on forests and washes away the nutrients in the soil. Since not all of the sulfur dioxide converts to sulfuric acid, the gas floats in the air and clogs up the stomata in the leaves stopping photosynthesis from occurring. Acid rain also causes rivers and lakes to become acidic.
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