Enter your answer in the provided box. Consider the reaction H2(g) + Cl2(g) → 2HCl(g)ΔH = −184.6 kJ / mol If 2.00 moles of H2 react with 2.00 moles of Cl2 to form HCl, what is ΔU (in kJ) for this reaction at 1.0 atm and 25°C? Assume the reaction goes to completion.

Respuesta :

Answer : The value of [tex]\Delta E[/tex] of the reaction is, -369.2 KJ

Explanation :

Formula used :

[tex]\Delta E=\Delta H-\Delta n_g\times RT[/tex]

where,

[tex]\Delta E[/tex] = internal energy of the reaction = ?

[tex]\Delta H[/tex] = enthalpy of the reaction = -184.6 KJ/mole = -184600 J/mole

The balanced chemical reaction is,

[tex]H_2(g)+Cl_2(g)\rightarrow 2HCl(g)[/tex]

when the moles of [tex]H_2\text{ and }Cl_2[/tex] are 2 moles then the reaction will be,

[tex]2H_2(g)+2Cl_2(g)\rightarrow 4HCl(g)[/tex]

From the given balanced chemical reaction we conclude that,

[tex]\Delta n_g[/tex] = change in the moles of the reaction = Moles of product - Moles of reactant = 4 - 4 = 0 mole

R = gas constant = 8.314 J/mole.K

T = temperature = [tex]25^oC=273+25=298K[/tex]

Now put all the given values in the above formula, we get:

[tex]\Delta E=(-184600J/mole\times 2mole)-(0mole\times 8.314J/mole.K\times 298K)[/tex]

[tex]\Delta E=-369200J[/tex]

[tex]\Delta E=-369.2KJ[/tex]

Therefore, the value of [tex]\Delta E[/tex] of the reaction is, -369.2 KJ