answersLogoWhite

0


Best Answer

enthalpy H i the sum of the internal energy U and the 'pV-energy'= p*V.

The pV term is also called flow-energy, pressure-energy or energy of displacement. The p is the external pressure, but for systems at constant pressure it is also equal to the internal pressure. Hence: H=U+pV.

It follows that H is a composite form of energy, a statement not commonly found in the literature.

>> 'Energy-balance of the Joule-Thomson experiment: Enthalpy change at decompression.' (NPT-procestechnologie, 2010, 17(4)18-22)

User Avatar

Wiki User

13y ago
This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: Could you give me an equation for enthalpy?
Write your answer...
Submit
Still have questions?
magnify glass
imp
Related questions

How do you solve Hess's law problems?

To solve Hess's law problems, first write out the chemical equations for all reactions involved. Then calculate the enthalpy change for each reaction. Finally, add or subtract the enthalpy changes to obtain the overall enthalpy change for the desired reaction.


What could make Delta become negative at a given enthalpy and entropy?

The equation for ∆G is ∆G = ∆H - T∆S H is enthalpy and S is entropySo, ∆G is negative if T∆S is greater than ∆H


Which equation do you use to calculate the enthalpy of neutralisation from an acid-base reaction?

yea


Give me a sentence with the word 'equation'?

"Try as he might, he could not solve the equation."


What is delta h in the equation delta g delta h - t delta s?

Delta H represents the change in enthalpy of a system. In the equation ΔG = ΔH - TΔS, it is the enthalpy change of the system. It indicates the heat absorbed or released during a reaction at constant pressure.


What is the enthalpy change to burn 37.5 g of ammonia?

The enthalpy change to burn 37.5 g of ammonia (NH3) can be calculated using the standard enthalpy of formation of ammonia and the balanced chemical equation for its combustion. The enthalpy change will depend on the specific conditions of the reaction, such as temperature and pressure.


Ethanol CH3CHO - how to write an equation to represent the enthalpy of formation?

The enthalpy of formation equation for Ethanol (CH3CH2OH) can be written as: CH3CH2OH (l) -> C2H5OH (l) + 3/2 O2 (g) This equation represents the formation of 1 mol of Ethanol from its elements in their standard states at 25°C and 1 atm pressure.


What is a chemical equation that includes the enthalpy change?

One example of a chemical equation that includes the enthalpy change is the combustion of methane: CH4(g) + 2O2(g) → CO2(g) + 2H2O(l) ΔH = -802.3 kJ. In this reaction, 802.3 kJ of heat is released as the products are formed.


Where does heat appear in the equation?

Heat appears in the equation as either a reactant (if heat is added to the reaction) or as a product (if heat is released by the reaction). It is typically denoted by the symbol "ΔH" for the change in enthalpy.


How is the enthalpy of reaction related to the enthalpies of formation for the products and reactants?

The difference between the enthalpy of formation of the products minus the enthalpy of formation of the reactants is the enthalpy of the reaction


What could make delta G become negative at a given enthalpy and entropy?

For delta G to become negative at a given enthalpy and entropy, the process must be spontaneous. This can happen when the increase in entropy is large enough to overcome the positive enthalpy, leading to a negative overall Gibbs free energy. This typically occurs at higher temperatures where entropy effects dominate.


How do you calculate enthalpy given the temperature?

Specific Heat is:-the amount of energy required to raise the temperature of 1g of a substance 1°C-specific heat is symbolised as Cp or C-has units of J/g °C-J stands for Joules, which is a unit of energyMost often used in equation: q = mΔTCpq = energy in Jm = mass in gΔT = change in temperatureCp = specific heatExampleHow much energy is required to raise the temperature of 345.34g of Aluminium from 35.0°C to 250.00°C ? The specific heat of Aluminium is .90 J/Cp q = mΔTCpq = 345.34g(250.00°C - 35.0°C)0.09J/g°Cfrom there its just simple Algebra.q = 66,823.29JHowever, not all problems will be as simple as the one above. Some may require up to 3+ equations that can include Enthalpy or ΔH which leads to using a Change of State Graph.