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    the boltzmann equation is given by Ni/N0 = exp (-Ei/RT) where Ni is the number of atoms or molecules in a state with energy Ei and N0 is the number of atoms or molecules in the lowest energy state with zero energy. At 1000k, what % of the molecules are in a state i with an energy of 5KJmol-1 assuming both levels have the same degeneracy

    anyone know how to do this?
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    You already have the equation required.

    \dfrac{N_i}{N_0}=e^{-\frac{E_i}{kT}}

    You know E_i, k and T. Just make sure you have everything with the right units and that gives you the ratio of atoms/molecules in state i to state 0.

    To find out the proportion of total molecules in state i you need more information.
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    (Original post by alow)
    You already have the equation required.

    \dfrac{N_i}{N_0}=e^{-\frac{E_i}{kT}}

    You know E_i, k and T. Just make sure you have everything with the right units and that gives you the ratio of atoms/molecules in state i to state 0.

    To find out the proportion of total molecules in state i you need more information.
    I just get an error when i do exp (5000/1000 x 138065x10^-23)
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    (Original post by jacksonmeg)
    I just get an error when i do exp (5000/1000 x 138065x10^-23)
    You forgot the - sign, and check your units.
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    (Original post by alow)
    You forgot the - sign, and check your units.
    now i got 0
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    (Original post by jacksonmeg)
    now i got 0
    Check your units.
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    (Original post by alow)
    Check your units.
    i converted energy to j mol-1, temperature in kelvin and boltzmann constant in J K-1 i dont see whats wrong
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    (Original post by jacksonmeg)
    i converted energy to j mol-1, temperature in kelvin and boltzmann constant in J K-1 i dont see whats wrong
    You need to cancel the mol.
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    (Original post by alow)
    You need to cancel the mol.
    so just put 6.022x10^-23 on the denominator
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    (Original post by jacksonmeg)
    so just put 6.022x10^-23 on the denominator
    You want Avogadros number on the numerator.
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    (Original post by alow)
    You want Avogadros number on the numerator.
    then i get 0 again
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    (Original post by jacksonmeg)
    then i get 0 again
    Yeah easier to use R.


    \dfrac{N_i}{N_0}=e^{-\frac{E_i}{RT}}= e^{-\dfrac{5000\text{Jmol}^{-1}}{8.31  \text{JK}^{-1}\text{mol}^{-1} \cdot 1000\text{K}}}=0.548
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    Is this like university level physics because I've not understood the last 2 threads you've put up.


    Posted from TSR Mobile
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    (Original post by RossB1702)
    Is this like university level physics because I've not understood the last 2 threads you've put up.


    Posted from TSR Mobile
    It's probably second year Chemistry.
 
 
 
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