Examples of chemical equilibrium
Here are a few simple examples of chemical equilibrium.
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Dissolving Sugar in Water: When you add sugar to a glass of water and stir it, the sugar dissolves. However, there's a point where no more sugar can dissolve in the water, and you'll see sugar crystals at the bottom of the glass. At this stage, you have a dynamic equilibrium between the dissolved sugar molecules and the undissolved sugar crystals.
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Water Evaporation: If you leave a glass of water exposed to air, the water molecules will gradually evaporate into vapor. Eventually, you'll reach a point where the rate of water molecules evaporating equals the rate at which water vapor condenses back into the liquid. This is a dynamic equilibrium between the liquid and vapor phases of water.
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Synthesis of Ammonia: In industrial processes, ammonia (NH3) is synthesized from nitrogen (N2) and hydrogen (H2) gases. Initially, as the reaction starts, ammonia production is slow. But as more ammonia is formed, some of it decomposes back into nitrogen and hydrogen. At a certain point, the forward and reverse reactions occur at the same rate, leading to chemical equilibrium.
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Hemoglobin and Oxygen: In our blood, hemoglobin binds with oxygen to transport it throughout the body. When oxygen levels are high (e.g., in the lungs), hemoglobin binds with oxygen. When oxygen levels are low (e.g., in body tissues), hemoglobin releases oxygen. This is an example of a biological equilibrium.