The specific heat of water is relatively high eg

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The specific heat of water is relatively high e.g., Ethanol (drinking alcohol) = 0.6 cal/g/ o C e.g., Iron = 0.1 cal/g/ o C The frying pan full of water example. Why does water have a high specific heat? H bonds H bonds make it difficult to move water molecules (difficult to increase their kinetic energy) because the molecules are attached to one another. Since they are difficult to move, more input of energy is required to make them move, i.e., increase the temperature of the water.
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Santa Barbara 73° Los Angeles (Airport) 75° Pacific Ocean 68° Santa Ana 84° Burbank 90° San Bernardino 100° Palm Springs 106° Riverside 96° San Diego 72° 40 miles 70s (°F) 80s 90s 100s What does all this have to do with living comfortably on Earth? Among other things, the huge amount of water in oceans absorbs much of the heat from the sun without getting hot (no huge increase in temperature) As a result oceans: (1) ameliorate adjacent of land environments for land creatures (2) stabilize the living environment for sea creatures High “specific heat” (cal/g/ o C) of water
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Vaporization (Evaporation) Slow moving (low kinetic energy) liquid molecules Fast moving (high kinetic energy) gas molecules Evaporation follows the Law of Energy Conservation —if one thing gains energy, another must lose it. Heat of Vaporization is the amount of heat a liquid must absorb for 1g of it to be converted to the gaseous state. For water it is a lot: 580 cal (2x alcohol or ammonia) Why so much? You guessed it! H bonds – the water molecules resist movement. Also, by the law of energy conservation , when water molecules become gas they take a large amount of heat from the liquid with them, as expressed by their high kinetic energy (rapid movement) When water gas condenses, the high kinetic energy of the gas molecules is transferred to the surrounding air molecules.
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Water’s role in heating and cooling the Earth, continued Tropical oceans and smaller water bodies absorb great heat from the sun; some of this heat moves to the atmosphere as fast moving water molecules evaporate and join the other air gasses; the moist tropical air circulates to the poles and mountains, where the water molecules transfer their heat to surrounding air molecules as they condense to rain. Water molecules with high kinetic energy move to the air as water in lakes and oceans evaporates. This pulls heat from those lakes and oceans. Water molecules transfer their high kinetic energy to surrounding air molecules as they condense to liquid (rain). The surrounding air is thus warmed as O 2 and N 2 pick up kinetic energy from the condensing
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Water’s role in heating and cooling us Why do we sweat? To cool our skin through evaporation. Sweat-water evaporates from the skin, taking body heat with it. Thus, heat is transferred away from to the body and into the surrounding air.
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