Specific Heat - Revision history

Laurence12799: /* Einstein-Debye Model */

2019-08-02T13:48:57Z

Einstein-Debye Model

← Older revision		Revision as of 09:48, 2 August 2019
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	:::::::::::<math>C \approx \frac{3N_{A}k_{B}\left(\frac{hv}{k_{B}T}\right)^2 \left(1 + \frac{hv}{k_{B}T} \right)}{\left(\frac{hv}{k_{B}T} \right)^2} \ mole^{-1}</math>		:::::::::::<math>C \approx \frac{3N_{A}k_{B}\left(\frac{hv}{k_{B}T}\right)^2 \left(1 + \frac{hv}{k_{B}T} \right)}{\left(\frac{hv}{k_{B}T} \right)^2} \ mole^{-1}</math>

	:::::::::::<math>C \approx 3N_{A}k_{B}\left(1 + \frac{hv}{k_{B}T} \right) \approx 3N_{A}k_{B} \ mole^{-1}</math>		:::::::::::<math>C \approx 3N_{A}k_{B}\left(1 + \frac{hv}{k_{B}T} \right) mole^{-1} \approx 3N_{A}k_{B} \ mole^{-1}</math>

	===Computational Model===		===Computational Model===

Laurence12799: /* Connectedness */

2019-08-02T13:48:25Z

Connectedness

← Older revision		Revision as of 09:48, 2 August 2019
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	[[File:jedandva.jpg.png\|center]]		[[File:jedandva.jpg.png\|center]]
	~~(Illustration of the hydrogen bonds in water)~~

	This is not an exclusive trait to water, however. The stronger the intermolecular forces of an object, generally the higher the specific heat capacity. Traditionally, gases and liquids have a higher specific heat capacity than solids. In addition, specific heat capacity is also related to the amount of kinetic energy possible in a molecule. Therefore, molecules with more available movement(liquids and gases), there is more room for the heat to "go". Because it is related to kinetic energy, as the external temperature approaches absolute zero, so does specific heat capacity.		This is not an exclusive trait to water, however. The stronger the intermolecular forces of an object, generally the higher the specific heat capacity. Traditionally, gases and liquids have a higher specific heat capacity than solids. In addition, specific heat capacity is also related to the amount of kinetic energy possible in a molecule. Therefore, molecules with more available movement(liquids and gases), there is more room for the heat to "go". Because it is related to kinetic energy, as the external temperature approaches absolute zero, so does specific heat capacity.

Laurence12799: /* Connectedness */

2019-08-02T13:47:55Z

Connectedness

← Older revision		Revision as of 09:47, 2 August 2019
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	It is easy to notice that water's specific heat capacity is much larger than anything else, but why? The answer is due to water's intermolecular forces. Since a water molecule is made up of one oxygen atom(negative charge) and two hydrogen atoms(slight positive charges), water has hydrogen bonds which result in the "sticking" of water molecules. Because of these hydrogen bonds, it requires a lot of energy to heat up water molecules, because not only do you have to use energy to increase the movement of the particle, but also to break the hydrogen bonds. As a result water has a high specific heat capacity because it takes a lot of energy to break the hydrogen bonds.		It is easy to notice that water's specific heat capacity is much larger than anything else, but why? The answer is due to water's intermolecular forces. Since a water molecule is made up of one oxygen atom(negative charge) and two hydrogen atoms(slight positive charges), water has hydrogen bonds which result in the "sticking" of water molecules. Because of these hydrogen bonds, it requires a lot of energy to heat up water molecules, because not only do you have to use energy to increase the movement of the particle, but also to break the hydrogen bonds. As a result water has a high specific heat capacity because it takes a lot of energy to break the hydrogen bonds.

	[[File:jedandva.jpg.png]]		[[File:jedandva.jpg.png\|center]]
	(~~illustration~~ of the hydrogen bonds in water)		(Illustration of the hydrogen bonds in water)

	This is not an exclusive trait to water, however. The stronger the intermolecular forces of an object, generally the higher the specific heat capacity. Traditionally, gases and liquids have a higher specific heat capacity than solids. In addition, specific heat capacity is also related to the amount of kinetic energy possible in a molecule. Therefore, molecules with more available movement(liquids and gases), there is more room for the heat to "go". Because it is related to kinetic energy, as the external temperature approaches absolute zero, so does specific heat capacity.		This is not an exclusive trait to water, however. The stronger the intermolecular forces of an object, generally the higher the specific heat capacity. Traditionally, gases and liquids have a higher specific heat capacity than solids. In addition, specific heat capacity is also related to the amount of kinetic energy possible in a molecule. Therefore, molecules with more available movement(liquids and gases), there is more room for the heat to "go". Because it is related to kinetic energy, as the external temperature approaches absolute zero, so does specific heat capacity.
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	A large body of water can absorb and store a huge amount of heat from the sun in the daytime, such as during summer, while only warming up a few degrees. During night and Winter, the gradually cooling water can warm the air. This is the reason coastal areas generally have milder climates than inland rtegions. The high specific heat of water also tends to stabilize ocean temperatures, creating a favorable environment for marine life. Thus because of its high specific heat, the water that covers most of Earth keeps temperature fluctuations on land and in water within limits that permit life. Also, because organisms are primarily made of water, they are more able to resist changes in their own temperature than if they were made of a liquid with a lower specific heat.		A large body of water can absorb and store a huge amount of heat from the sun in the daytime, such as during summer, while only warming up a few degrees. During night and Winter, the gradually cooling water can warm the air. This is the reason coastal areas generally have milder climates than inland rtegions. The high specific heat of water also tends to stabilize ocean temperatures, creating a favorable environment for marine life. Thus because of its high specific heat, the water that covers most of Earth keeps temperature fluctuations on land and in water within limits that permit life. Also, because organisms are primarily made of water, they are more able to resist changes in their own temperature than if they were made of a liquid with a lower specific heat.

	Specific heat and ~~thermodynamics~~ are used often in chemistry, nuclear engineering, aerodynamics, and mechanical engineering. It is also used in everyday life in the radiator and cooling system of a car.		Specific heat and Thermodynamics are used often in chemistry, nuclear engineering, aerodynamics, and mechanical engineering. It is also used in everyday life in the radiator and cooling system of a car.

	Specific heat can have a lot to do with prosthetic manufacturing, which is a focus in Biomedical Engineering. Prosthetics materials must be durable and easy to manipulate in a normal range of temperatures. In order to created medical devices, specific heats must be known, especially for welding or molding things, which require a specific temperature to be effective. At higher temperatures, the Dulong-Petit law must be used to calculate the specific heat of an object. Especially for solid metal objects, which would be used in prosthetics, Dulong-Petit is very useful.		Specific heat can have a lot to do with prosthetic manufacturing, which is a focus in Biomedical Engineering. Prosthetics materials must be durable and easy to manipulate in a normal range of temperatures. In order to created medical devices, specific heats must be known, especially for welding or molding things, which require a specific temperature to be effective. At higher temperatures, the Dulong-Petit law must be used to calculate the specific heat of an object. Especially for solid metal objects, which would be used in prosthetics, Dulong-Petit is very useful.

Laurence12799: /* Connectedness */

2019-08-02T13:41:10Z

Connectedness

← Older revision		Revision as of 09:41, 2 August 2019
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	The '''Specific Heat Capacity''' most commonly known is the '''Specific Heat Capacity''' of water, which is about 4.12 J/g°C or 1 calorie/g°C. The specific heat of water is higher than any other common substance. Water has a very large specific heat on a per-gram basis, meaning that it takes a lot more added heat to cause a change in its temperature. Since the specific heat of water is so high, water can be used for temperature regulation. Due to the difference in atomic structures, the specific heat per gram of water is much higher than that of a metal substance. It is possible to predict the specific heat of any material, as long as you know about its atomic structure, as a rise in temperature is the increase in energy at the atomic level of substances. Generally, it is more more useful to compare molar specific heats of substances.		The '''Specific Heat Capacity''' most commonly known is the '''Specific Heat Capacity''' of water, which is about 4.12 J/g°C or 1 calorie/g°C. The specific heat of water is higher than any other common substance. Water has a very large specific heat on a per-gram basis, meaning that it takes a lot more added heat to cause a change in its temperature. Since the specific heat of water is so high, water can be used for temperature regulation. Due to the difference in atomic structures, the specific heat per gram of water is much higher than that of a metal substance. It is possible to predict the specific heat of any material, as long as you know about its atomic structure, as a rise in temperature is the increase in energy at the atomic level of substances. Generally, it is more more useful to compare molar specific heats of substances.

	The ~~study of Thermodynamics was largely sparked by research done on '''Specific Heat Capacity''~~'. ~~Thermodynamics~~ is the ~~study~~ of ~~the conversion~~ of energy ~~involving~~ the ~~Heat and Temperature change~~ of a ~~system~~.		It is easy to notice that water's specific heat capacity is much larger than anything else, but why? The answer is due to water's intermolecular forces. Since a water molecule is made up of one oxygen atom(negative charge) and two hydrogen atoms(slight positive charges), water has hydrogen bonds which result in the "sticking" of water molecules. Because of these hydrogen bonds, it requires a lot of energy to heat up water molecules, because not only do you have to use energy to increase the movement of the particle, but also to break the hydrogen bonds. As a result water has a high specific heat capacity because it takes a lot of energy to break the hydrogen bonds.

	[[File:~~Zvezda12~~.jpg~~\|400px~~]]		[[File:jedandva.jpg.png]]
			(illustration of the hydrogen bonds in water)
	It is easy to notice that water's specific heat capacity is much larger than anything else, but why? The answer is due to water's intermolecular forces. Since a water molecule is made up from one oxygen atom(negative charge) and two hydrogen atoms(~~slight positive charges), water has hydrogen bonds which result in the "sticking"~~ of water molecules. Because of these hydrogen bonds it requires a lot of energy to heat up water molecules, because not only do you have to use energy to increasing the movement of the particle, but also to break the hydrogen bonds~~. As a result~~ water ~~has a high specific heat capacity because it takes a lot of energy to break the hydrogen bonds.~~

	This is not an exclusive trait to water, however. The stronger the intermolecular forces of an object, generally the higher the specific heat capacity. Traditionally, gases and liquids have a higher specific heat capacity than solids. In addition, specific heat capacity is also related to the amount of kinetic energy possible in a molecule. Therefore, molecules with more available movement(liquids and gases), there is more room for the heat to "go". Because it is related to kinetic energy, as the external temperature approaches absolute zero, so does specific heat capacity.		This is not an exclusive trait to water, however. The stronger the intermolecular forces of an object, generally the higher the specific heat capacity. Traditionally, gases and liquids have a higher specific heat capacity than solids. In addition, specific heat capacity is also related to the amount of kinetic energy possible in a molecule. Therefore, molecules with more available movement(liquids and gases), there is more room for the heat to "go". Because it is related to kinetic energy, as the external temperature approaches absolute zero, so does specific heat capacity.

	~~[[File:jedandva.jpg.png]]~~
	~~(illustration of the hydrogen bonds in water)~~

	But why is this important?		But why is this important?

	A large body of water can absorb and store a huge amount of heat from the sun in the daytime ~~and~~ during summer while warming up ~~only~~ a few degrees. ~~And at~~ night and ~~during winter~~, the gradually cooling water can warm the air. This is the reason coastal areas generally have milder climates than inland rtegions. The high specific heat of water also tends to stabilize ocean temperatures, creating a favorable environment for marine life. Thus because of its high specific heat, the water that covers most of Earth keeps temperature fluctuations on land and in water within limits that permit life. Also, because organisms are primarily made of water, they are more able to resist changes in their own temperature than if they were made of a liquid with a lower specific heat.		A large body of water can absorb and store a huge amount of heat from the sun in the daytime, such as during summer, while only warming up a few degrees. During night and Winter, the gradually cooling water can warm the air. This is the reason coastal areas generally have milder climates than inland rtegions. The high specific heat of water also tends to stabilize ocean temperatures, creating a favorable environment for marine life. Thus because of its high specific heat, the water that covers most of Earth keeps temperature fluctuations on land and in water within limits that permit life. Also, because organisms are primarily made of water, they are more able to resist changes in their own temperature than if they were made of a liquid with a lower specific heat.

	Specific heat and thermodynamics are used often in chemistry, nuclear engineering, aerodynamics, and mechanical engineering. It is also used in everyday life in the radiator and cooling system of a car.		Specific heat and thermodynamics are used often in chemistry, nuclear engineering, aerodynamics, and mechanical engineering. It is also used in everyday life in the radiator and cooling system of a car.

Laurence12799: /* External links */

2019-08-02T13:29:38Z

External links

← Older revision		Revision as of 09:29, 2 August 2019
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	*[http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/spht.html HyperPhysics Specific Heat]<br>		*[http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/spht.html HyperPhysics Specific Heat]<br>
	*[https://en.wikipedia.org/wiki/Heat_equation Wikipedia: Heat Equation]<br>		*[https://en.wikipedia.org/wiki/Heat_equation Wikipedia: Heat Equation]<br>
	*[http://oceanservice.noaa.gov/education/pd/oceans_weather_climate/media/specific_heat.swf]<br>		*[http://oceanservice.noaa.gov/education/pd/oceans_weather_climate/media/specific_heat.swf Specific Heat Simulation]<br>

	==References==		==References==

Laurence12799 at 13:29, 2 August 2019

2019-08-02T13:29:07Z

Show changes

Laurence12799: /* Einstein-Debye Model */

2019-08-02T12:46:31Z

Einstein-Debye Model

← Older revision		Revision as of 08:46, 2 August 2019
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	For high temperatures it may be reduced like this:		For high temperatures it may be reduced like this:

	:::::::::::<math>C \approx \frac{3N_{A}k_{B}\left(\frac{hv}{k_{B}T}\right)^2 \left(1 + \frac{hv}{k+{B}T} \right)}{\left(\frac{hv}{k_{B}T} \right)^2} \ mole^{-1}</math>		:::::::::::<math>C \approx \frac{3N_{A}k_{B}\left(\frac{hv}{k_{B}T}\right)^2 \left(1 + \frac{hv}{k_{B}T} \right)}{\left(\frac{hv}{k_{B}T} \right)^2} \ mole^{-1}</math>

	:::::::::::<math>C \approx 3N_{A}k_{B}\left(1 + \frac{hv}{k_{B}T} \right) \approx 3N_{A}k_{B} \ mole^{-1}</math>		:::::::::::<math>C \approx 3N_{A}k_{B}\left(1 + \frac{hv}{k_{B}T} \right) \approx 3N_{A}k_{B} \ mole^{-1}</math>

Laurence12799: /* See also */

2019-08-02T03:04:54Z

Laurence12799: /* Law of Dulong and Petit */

2019-08-02T03:03:17Z

Law of Dulong and Petit

← Older revision		Revision as of 23:03, 1 August 2019
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	The Law of Dulong and Petit is a Thermodynamic law discovered in 1819 by the French physicists Pierre Louis Dulong and Alexis Thérèse Petit. It yields the expression for the Molar Specific Heat Capacity of certain chemical elements. They found, through experiments, that the Mass Specific Heat Capacity for many elements was close to a constant value, after it had been adjusted to reflect the relative atomic weight of the element.		The Law of Dulong and Petit is a Thermodynamic law discovered in 1819 by the French physicists Pierre Louis Dulong and Alexis Thérèse Petit. It yields the expression for the Molar Specific Heat Capacity of certain chemical elements. They found, through experiments, that the Mass Specific Heat Capacity for many elements was close to a constant value, after it had been adjusted to reflect the relative atomic weight of the element.

	Basically, Dulong and Petit found that the '''Specific Heat Capacity''' of a mole of numerous solid elements is about 3R, where R is the universal gas constant. Dulong and Petit were unaware of the relationship to R, since it had not yet been defined. The value of 3R is about <math>25 \ \frac{J}{mol \cdot K}</math>, and Dulong and Petit found that this was the approximate Heat Capacity of some solid elements per mole of atoms they contained.		Basically, Dulong and Petit found that the '''Specific Heat Capacity''' of a mole of numerous solid elements is about 3R, where R is the universal gas constant. Dulong and Petit were unaware of the relationship to R, since it had not yet been defined. The value of 3R is about <math>25 \ \frac{J}{mol \cdot K}</math>, and Dulong and Petit found that this was the approximate Molar Specific Heat Capacity of some solid elements per mole of atoms they contained.

	:For example, The '''Specific Heat Capacity''' of copper is <math>0.385 \ \frac{J}{g \cdot K}</math>. The '''Specific Heat Capacity''' of lead is <math>0.128 \ \frac{J}{g \cdot K}</math>. Why are the values so different in these two metals? Did you notice that they are expressed as energy per unit mass? If you express each as energy per mole, they are actually very similar. The Law of Dulong and Petit addresses this similarity in molar specific heats. It can be accounted for by applying equipartition of energy to the atoms of solids:		:For example, The '''Specific Heat Capacity''' of copper is <math>0.385 \ \frac{J}{g \cdot K}</math>. The '''Specific Heat Capacity''' of lead is <math>0.128 \ \frac{J}{g \cdot K}</math>. Why are the values so different in these two metals? Did you notice that they are expressed as energy per unit mass? If you express each as energy per mole, they are actually very similar. The Law of Dulong and Petit addresses this similarity in molar specific heats. It can be accounted for by applying equipartition of energy to the atoms of solids:

Laurence12799: /* References */

2019-08-02T03:01:38Z

References

← Older revision		Revision as of 23:01, 1 August 2019
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	===External links===		===External links===

	==References==		==References==.
	The specific heat for solid can be calculated by the change in energy of the atoms over the change in temperature. The change in energy of the atoms is calculated by dividing the change in the energy of the system by the number of atoms in the substance.

	There are two models to determine the specific heats of substances at an atomic level. These are the Dulong-Petit Law and the Einstein-Debye model. The Dulong-Petit Law states that the molar specific heats of most solids (at room temperature or above) are almost constant. The Einstein-Debye model of specific heat states that specific heats drop at lower temperatures, as atomic processes become more relevant.

	~~These are various specific heats of materials. Notice the difference of specific heat in the different phases of water~~.

	== See also ==		== See also ==

← Older revision		Revision as of 23:04, 1 August 2019
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	===External links===		===External links===

	==References==.		==References==

	== See also ==		== See also ==