Question

What is Hess's law of constant heat sublimation??​

Answer 1

Question :

What is Hess's law of constant heat sublimation??

Explanation:

Hess's Law. Hess's Law of Constant Heat Summation (or just Hess's Law) states that regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes. This law is a manifestation that enthalpy is a state function.

Answer 2

Explanation:

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What is Hess's law of constant heat sublimation..

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• Hess's law of constant sublimation

This law states that heat change accompanying a chemical reaction is same, weather the reaction takes place in a single step.

It means that value of heat change in a chemical reaction depends only upon the nature of initial reactants and final products and it is dependent on path.

For example, formation of CO2 from C in two different manners involved in total change of energy (heat)

Single step process :

C(s) + O2 (g) -----> CO2 (g)

Also ,

∆H1 for the above reaction is approximately -390 KJ/mol

Double step process :

(i) C(s) + 1/2 O2(g) ----> CO (g)

Also,

∆H for the above reaction is

approximately -110 KJ/mol

(ii) CO(g) + 1/2 O2 -----> CO2 (g)

Here,

∆H2 for above reaction is

approximately -280 KJ/mol

So, for two step process=>

∆H(total) = ∆H1 + ∆H2

= (- 110) + ( - 280)

= - 390 KJ / mol

So, for both the process ∆H value is same