Enthalpy vs heat
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Enthalpy vs heat
What is the difference between heat and enthalpy? I understand that they are connected, but in what ways do they differ?
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Re: Enthalpy vs heat
From my understanding, heat is the actual flow of energy when there is a temperature change whereas enthalpy is the change in heat absorbed or emitted at a constant pressure.
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Re: Enthalpy vs heat
Enthalpy is at constant pressure and is often equal to heat when there are no other factors at play to my understanding.
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Re: Enthalpy vs heat
Enthalpy basically measures the heat flow at a constant pressure. Since heat is not a state property at constant pressure, we can't really use it to reveal heat flow in a system. Therefore, enthalpy is an energy quantity that measures the amount of heat absorbed/released (which is what I meant when I said heat flow in the latter sentence) at constant pressure.
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Re: Enthalpy vs heat
Heat is a transfer of energy due to a temperature difference where as enthalpy is the change in amount of heat in a system at constant pressure.
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Re: Enthalpy vs heat
When pressure is not constant, heat is not a state property. Enthalpy is a state property.
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Re: Enthalpy vs heat
Enthalpy is a type of heat. The most important distinction is that enthalpy is when heat is transferred from the system to the surroundings or vice versa, at a constant pressure.
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Re: Enthalpy vs heat
Enthalpy is essential a concept formed to get heat as a state function. In order to do so there is the condition that the system is under constant pressure so that the path is defined.
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Re: Enthalpy vs heat
Enthalpy is the amount of heat released or absorbed at a constant pressure. Heat describes energy transfer.
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Re: Enthalpy vs heat
Lea Baskin Monk 1F wrote:What is the difference between heat and enthalpy? I understand that they are connected, but in what ways do they differ?
Heat is a measure of energy transfer, while enthalpy is the change in energy of the system.
So, in a way, heat is responsible for enthalpy.
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Re: Enthalpy vs heat
Heat is the transfer of energy between a system and its surroundings to a temperature difference while enthalpy is the change in amount of heat in a system at constant pressure.
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Re: Enthalpy vs heat
Heat is the amount of energy that is transferred between two systems because of an energy difference. Enthalpy is the sum of a system's internal energy and is the product of the system's volume and pressure.
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Re: Enthalpy vs heat
Enthalpy can be described as the internal energy of the system. It is the amount of heat energy that is absorbed or given off during a chemical reaction at a constant pressure. Enthalpy is also a state function, meaning the change can be determined additively. Heat, on the other hand, is a form of energy that flows from the system to its surroundings due to a difference in temperature (high to low). Generally, the change in heat can not be measured additively since it is not a state function. You would have to know the "path" taken to get a proper measurement.
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Re: Enthalpy vs heat
Heat is a transfer of energy due to a temperature difference. Enthalpy is the change in the amount of heat in a system at constant pressure. Remember that for these terms, you can only use heat and enthalpy interchangeably if there is no work being done to the system. Hope this helps!
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Re: Enthalpy vs heat
Enthalpy is at constant pressure and is a state property while heat is not. Hope this helps!
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Re: Enthalpy vs heat
Enthalpy refers to heat released or absorbed while heat describes a transfer of energy.
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Re: Enthalpy vs heat
Enthalpy is a state property that measures heat, whereas heat is the flow of energy
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Re: Enthalpy vs heat
Enthalpy is the state property that is used to measure the change in heat of the system while heat itself is the energy that is being transferred in or out when the temperature (also a state property) changes.
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Re: Enthalpy vs heat
Heat is the transfer of energy between two systems because of an energy difference while enthalpy measures the change of amount of heat in a system
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Re: Enthalpy vs heat
enthalpy is the change in heat within a system. heat is the transfer of energy between systems.
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Re: Enthalpy vs heat
heat is the flow of energy while enthalpy measures heat. enthalpy is a state property but heat is not
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Re: Enthalpy vs heat
Enthalpy is a state property, so its value is determined by its current state instead of the path taken to obtain that state. However, heat is dependent on the details of a path taken. If heat was at constant pressure, then the value would be the same as enthalpy.
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Re: Enthalpy vs heat
Enthalphy measures the heat flow at a constant pressure and heat would not be a state property at constant pressure which is why we wouldnt know the heat flow of a system. Enthalpy is the energy that measure the heart that is absorbed or released
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Re: Enthalpy vs heat
Enthalpy should be heat flow at a constant pressure. Heat is the general temperature of the reaction and the thermal energy of the reaction. Heat itself is also not a state property and can be changed/is more fickle and harder to measure.
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Re: Enthalpy vs heat
Heat is the measure of energy transferred from the system to the surroundings. Enthalpy is the change in internal energy of the system. Under constant pressure, the two are the same.
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Re: Enthalpy vs heat
Enthalpy is a state property and often represents one aspect of a system at a particular instant in time. It is represented in equations by the variable H. Conversely, heat is often described as something input into or taken out of a system. It is represented in equations by the variable q and is often used in calculations pertaining to changes in internal energy.
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Re: Enthalpy vs heat
Enthalpy is the change in the amount of heat in a system and heat is the transfer of energy as a result of temperature difference.
Re: Enthalpy vs heat
Heat is the transfer of energy due to a temperature difference while enthalpy is the change in the amount of heat in a system at constant pressure
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