
Respuesta :
Answer:
- 1273.02 kJ.
Explanation:
This problem can be solved using Hess's Law.
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.
- We should modify the given 3 equations to obtain the proposed reaction:
6C(s) + 6Hβ(g) + 3Oβ(g) β CβHββOβ(s),
- We should multiply the first equation by (6) and also multiply its ΞH by (6):
6C(s) + 6Oβ(g) β 6COβ(g), βHβ = (6)(β393.51 kJ) = - 2361.06 kJ,
- Also, we should multiply the second equation and its ΞH by (6):
6Hβ(g) + 3Oβ(g) β 6HβO(l), βHβ = (6)(β285.83 kJ) = - 1714.98 kJ.
- Finally, we should reverse the first equation and multiply its ΞH by (- 1):
6COβ(g) + HβO(l) β CβHββOβ(s) + 6Oβ(g), βHβ = (-1)(β2803.02 kJ) = 2803.02 kJ.
- By summing the three equations, we cam get the proposed reaction:
6C(s) + 6Hβ(g) + 3Oβ(g) β CβHββOβ(s),
- And to get the heat of reaction for the production of glucose, we can sum the values of the three βH:
βHrxn = βHβ + βHβ + βHβ = (- 2361.06 kJ) + (- 1714.98 kJ) + (2803.02 kJ) = - 1273.02 kJ.