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First, let us understand high specific heat with a simple example
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Imagine you are at a beach on a sunny day. The sand under your feet is scorching hot while the ocean water is still cold
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This is because sand has a lower specific heat, it heats up and cools down quickly while
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water has high specific heat that takes much longer to change its temperature
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This property of water to resist changes in temperature is called high specific heat capacity
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Or in other words, it takes a lot of heat to increase the temperature of liquid water
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because the hydrogen bonding between water molecules is very strong. Or high amount of heat is required to break hydrogen bonds between water molecules
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The high specific heat of water is approximately 4.18 joules per gram per degree Celsius
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That means it takes 4.18 joules of energy to raise the temperature of 1 gram of water
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by 1 degree Celsius. This is significantly higher than most other substances
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Take the case of sand, it has only 0.84 joules per gram degree Celsius
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Large water bodies like oceans and lakes absorb heat from the sun during the day without changing
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the temperature or without temperature rise drastically. At night when the air cools down, the water slowly releases stored heat, maintaining a
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moderate climate in coastal areas. Now let us discuss high heat of vaporization
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It refers to the amount of energy needed to change 1 gram of a liquid substance to a gas
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at constant temperature. Let's take a simple example. Let's compare ethanol and water
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To convert water, liquid water to gas or the boiling point, the heat of vaporization value
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is 40.65 kilojoules per molecule or at 100 degree Celsius. That's the water's boiling point
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Whereas the boiling point of ethanol is 78.3 degree Celsius. That means hydrogen bonds in ethanol is weak compared to the hydrogen bond between molecules
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in water or more heat energy is required to break the hydrogen bonds to convert it in
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from liquid state to the gaseous state. Let's take one more example
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When we exercise, on a hot day our body sweats, the water on our skin absorbs the heat from
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our body and evaporates turning from liquid to gas. This process of evaporation requires a lot of heat that is due to water's high heat of vaporization
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As the sweat evaporates, it takes away heat from our body, helping to cool us down called
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evaporative cooling. Or high amount of energy or heat is required to change water in liquid form to vapor or
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gaseous state. In humans and other organisms, the evaporation of sweat, which is about 99% water, cools
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the body to maintain a steady temperature. Hope you are clear with the difference between high heat of vaporization and high specific
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heat capacity of water. Take care, stay blessed. Thank you so much
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