Find mass of product when given Kc, mass of reactant, but not volume

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SUMMARY

The discussion focuses on calculating the mass of methylcyclopentane at equilibrium when given the equilibrium constant (Kc = 0.143) and the initial mass of cyclohexane (100 g). The equilibrium expression Kc = [product]/[reactant] is utilized, emphasizing that the volume of the solution is irrelevant for mass-based calculations. The key takeaway is that the mass of cyclohexane will decrease as it converts to methylcyclopentane, and the relationship between the masses can be established through the moles of each compound.

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Homework Statement


Assume that at 25 C, with AlCl3 as a catalyst, the following equilibrium can be established between the liquids cyclohexane and methylcyclopentane.
C6H12 <=> C5H9CH3HCH3
Kc = 0.143
If initially 1.00 x 10^2 g cyclohexane is present, what mass of methylcyclopentane will be present in the equilibrium mixture? (Hint: Does the volume of solution matter?)

Homework Equations



Kc = [product]/[reactant]

The Attempt at a Solution


I attempted to use ICE, but since I do not know the concentration (M) for the reactants, I do not know how to proceed.
I could get the moles of cyclohexane, but then don't I need to convert it to M?

Please advice. Thank you in advance.
 
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HINT: Does the Volume matter?
HINT2 : Does the mass matter? In a more abstract kinda way?

The thing is :

- moles initially of molecules (Cyclohex) = moles finally (Cyclohex + metpent)
- mass initially = mass finally
- and obviously Molecular mass of hex = Mol mass of pent
Kc=mass pentane/mass hexane=moles pentane/moles hexane.

So you end up with the amount % of hex that gets turned into pent.
 
Btw what is that:
C6H12 <=> C5H9CH3HCH3

the second isn't metylcyclopentane
 

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