Respuesta :
The balanced chemical eqaution for the given reaction:
2CH₄ + 5F₂ --> 2CF₄ + 2HF
The heats of formation of the compounds are as follows:
CH₄= -74.8kJ/mole
CF₄ = -925.0 kJ/mole
HF = -271.1 kJ/mole
0.29 moles CH₄ x (5 moles of F₂ / 2 moles of CH₄) = 0.725 moles F₂ required.
Given, moles of F₂ = 0.44
Therefore, F₂ is the limiting reactant
Now, F₂ will determine the moles of CF₄ and HF produced in the reaction.
0.44 moles of F₂ x (2 moles of CF₄/5 moles of F₂) = 0.176 moles CF₄
0.44 moles of F₂ x (2 moles of HF/5 moles of F₂) = 0.176 moles HF
Since the molar ratio between F₂: CF₄ and F₂: HF is 1:1
So 0.176 moles CF₄ and 0.176 moles HF will require 0.176 moles CH₄
ΔHrxn = ∑(moles x H products) - ∑ (moles x H reactants)
ΔHrxn = (0.176 x -271.1 kJ/mole + 0.176 x -925 kJ/mole) - (0.176 x -74.8 kJ/mole)
ΔHrxn = - 197.35 kJ
- 197.35 kJ of heat is released.
The reaction occurs at constant pressure, - 197.35 kJ amount of heat is released during reaction.
How we calculate released heat of the reaction?
Heat released of any reaction will be calculated as:
ΔH = ΔH of products - ΔH of reactants
Given chemical reaction is:
2CH₄ + 5F₂ → 2CF₄ + 2HF
From the stoichiometry of the reaction it is clear that,
2 moles of CH₄ = react with 5 moles of F₂
1 moles of CH₄ = react with 5/2 moles of F₂
So, 0.290 moles of CH₄ = react with 0.290×5/2=0.725 moles of F₂
Given moles of F₂ = 0.440 moles, which is less as compared to the calculated moles so for this reaction F₂ is the limiting reactant.
From the stoichiometry:
5 moles of F₂ = produce 2 moles of CF₄ & HF each
0.440 moles of F₂ = produce 2/5×0.440=0.176 moles of CF₄ & HF each
From the stoichiometry of the reaction it is also clear that, 0.176 moles of CF₄ & HF each require 0.176 moles of CH₄.
We know that, value of heat of formation of below molecules as:
CF₄ = -74.8kJ/mole
HF = -271.1 kJ/mole
CF₄ = -925.0 kJ/mole
F₂ = 0
Now we put all these value on the above equation with their respective moles, we get
ΔH = (0.176 x -271.1 kJ/mole + 0.176 x -925 kJ/mole) - (0.176 x -74.8 kJ/mole) = - 197.35 kJ
Hence, - 197.35 kJ amount of heat is released.
To know more about heat of reaction, visit the below link:
https://brainly.com/question/24376583
