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    Hi guys, could anyone help me with this Chem question, I feel like I'm massively overthinking something that should be pretty basic!
    I have this equation and info:
    CO(g)+ 2H2 (g) -->CH3OH(g)

    162.8 mol CO is added to 145 mol hydrogen. When equilibrium was reached the mixture contained 126.2 mol of methanol.

    How do I work out the mol of the reactants at equilibrium?
    I thought as CO and CH3OH are a 1:1 ratio, there's 36.6mol of CO at the end, but I don't know if this is right and I can't figure out the 2H2?

    Would really appreciate the help! (Even though it's no doubt a stupid question ) Thanks!
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    You have to factor in the balanced symbols. H2 has 1/2 of states moles really as this is the amount that reacts relative to within the system. So it is then the limiting reactant. The yells also may have a lower yield than theoretical. Theoretical is 100 percent which is nmoles (h2) / 2.

    Else if the numbers are correct.
    Equilibrium depends on the atmospheric conditions. The volume is usually constant or pressure constant and the other value varies (up or down we are told no numerical value will be given at AS usually) and the atom balance moves towards the appropriate side so that the system remains as close to the equilibrium conditions. (Lower total volume requires lower total moles to coefficients added up it will move to the side where the balanced symbol numbers will be lowest to fill a smaller volume).

    There is no set value it is dynamic therefore always changing.

    Use the rules above and try a few more times, if you cannot come up with a solution I will do the working out on a page and upload my answer!
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    2. Multiply the number of moles of all gases (36.6 + 126.6 ) and multiply by the molar gas constant and this is the volume of gases at dynamic equilibrium in this. Volume and pressure.

    If you have a photo of the question please supply it as this seems a little confusing as I can only pick out the above two answers from what was provided and I am thinking my second answer is the correct one.
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    (Original post by Anfanny)
    You have to factor in the balanced symbols. H2 has 1/2 of states moles really as this is the amount that reacts relative to within the system. So it is then the limiting reactant. The yells also may have a lower yield than theoretical. Theoretical is 100 percent which is nmoles (h2) / 2.

    Else if the numbers are correct.
    Equilibrium depends on the atmospheric conditions. The volume is usually constant or pressure constant and the other value varies (up or down we are told no numerical value will be given at AS usually) and the atom balance moves towards the appropriate side so that the system remains as close to the equilibrium conditions. (Lower total volume requires lower total moles to coefficients added up it will move to the side where the balanced symbol numbers will be lowest to fill a smaller volume).

    There is no set value it is dynamic therefore always changing.

    Use the rules above and try a few more times, if you cannot come up with a solution I will do the working out on a page and upload my answer!
    Thanks for the advice above, I've tried again but I am really not sure if I'm doing this right. So I thought as CO and CH3OH are a 1:1, then if there's 126.2 mol of CH3OH at equilibrium, then 126.2 of CO were used, leaving 36.6 mol at equilibrium. If CO and 2H2 have a 1:2 ratio, then is it just 36.6x2=73.2???




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    (Original post by Meera🦁)
    Thanks for the advice above, I've tried again but I am really not sure if I'm doing this right. So I thought as CO and CH3OH are a 1:1, then if there's 126.2 mol of CH3OH at equilibrium, then 126.2 of CO were used, leaving 36.6 mol at equilibrium. If CO and 2H2 have a 1:2 ratio, then is it just 36.6x2=73.2???




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    Usually one of the reactants is limiting in these types of questions so I would assume the only remaining gases are the excess carbon monoxide and the methanol in this state.

    Multiplied by the molar has constant should give you the volume in this equilibrium.

    I don't see any reason why hydrogen should be left over... So I think you are correct?

    But you need to say in what units do they want the answer, volume, amount of substance etc.
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    (Original post by Anfanny)
    Usually one of the reactants is limiting in these types of questions so I would assume the only remaining gases are the excess carbon monoxide and the methanol in this state.

    Multiplied by the molar has constant should give you the volume in this equilibrium.

    I don't see any reason why hydrogen should be left over... So I think you are correct?

    But you need to say in what units do they want the answer, volume, amount of substance etc.

    Thank you! I think I will use 76.3, the question is just the first stage of an equilibrium constant Kp question.
    I now can use the mols to work out the partial pressures, thanks very much!



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    Just remember 36.2 is what remains. And is not the total number of moles used up. Your hydrogen should be completely depleted.
 
 
 
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