Enthalpy and hess’ law, Chemistry

Assignment Help:

 

The enthalpy change (ΔH) in a reaction is equal to the heat input under conditions of constant pressure and temperature. It is not equal to the total energy change, as work may be done by expansion against the external pressure. The corrections are usually small, and enthalpy is used as a measure of the energies involved in chemical reactions. Endothermic reactions (positive ΔH) are ones need a heat input, and exothermic reactions (negative ΔH) give a heat output.

Hess' Law states that ΔH does not rely on the pathway taken between initial and final states, and is a consequence of the First Law of Thermodynamics, which asserts the conservation of total energy. It describes a schematic thermodynamic cycle where the ΔH can be expressed as the sum of the values for individual steps:

 

2056_Untitled.png


Related Discussions:- Enthalpy and hess’ law

Assignment, State 2nd law of thermodynamics in many forms as possible and s...

State 2nd law of thermodynamics in many forms as possible and show that they are identical in figures?

P block, why ionisation energy of aluminium is greater then Ga?

why ionisation energy of aluminium is greater then Ga?

Chemical properties of cycloalkanes, Chemical properties of Cycloalkanes ...

Chemical properties of Cycloalkanes Cycloalkanes behave both such as alkenes and alkanes in their chemical properties. All cycloalkanes go through substitution reaction with ha

Iupac nameing, Sir any method to learn the arrangement of functional group ...

Sir any method to learn the arrangement of functional group in poly functional compound ????

Molecar symetry, Explain significance of orthogonality rule

Explain significance of orthogonality rule

Electromeric effect - organic chemistry, Electromeric effect (1) The oc...

Electromeric effect (1) The occurrence of movement of electrons from one atom to other in multi bonded atoms at the demand of attacking reagent is known as electromeric effect.

#titleplease help.., Ask question #Minimum 100 words accepted Is there a se...

Ask question #Minimum 100 words accepted Is there a sequential move from one to another, amongst law, theory, and a hypothesis? Describe controlled conditions to find a scientific

Fire accident in an industry., If there is a fire accident in an industry, ...

If there is a fire accident in an industry, what  a safety enginner will do? Ans) Fire engineering is the application of engineering and science principles to protect prope

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd