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The procedure was performed to determine at which temperature the most dissolved oxygen is present. It was proposed that if the temperature is above room temperature (approximately 20°C), then the dissolved oxygen level will be relatively high. Dissolved oxygen is found in tiny, microscopic bubbles of oxygen, which occur between water molecules. Dissolved oxygen is created in water by the respiration and decomposition of organic matter. It is also made by the atmosphere and photosynthesis. Oxygen enters the water by absorption directly from the atmosphere or by photosynthesis occurring in aquatic plant and

Water temperature is an important aspect in the regulation of water's oxygen levels, because as temperature increases the oxygen saturation point of water decreases. This lab introduced concepts regarding dissolved oxygen and its importance to ecosystems as it relates to the survival of aquatic life. The water may not have had enough time to absorb the oxygen while it was being cooled or heated and there were also possible mistakes made while performing the experiment. 4 ppm of dissolved oxygen at 20 C, 10 ppm of dissolved oxygen at 4 C, and 8. Materials: -beakers -hot plate -ice bath -thermometers -see Lamotte kitProcedure: 1. 2Analysis and Conclusion: In this experiment the independent variable was temperature, the dependant variable was the dissolved oxygen level, the control was dissolved oxygen levels under normal conditions and all other variables were kept constant. Collect water samples from the three beakers at different temperatures (room temperature 20 C, cold 5 C, and hot 55 C). Dissolved oxygen is an important indicator of a body of water"tms ability to support aquatic life, because fish respire by absorbing dissolved oxygen through their gills. The hypothesis was not supported, probably due to the fact that the hypothesis was made without extended knowledge of the topic.