Equation balance help

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metalgearrex21
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Equation balance help

Post by metalgearrex21 »

Hi,

Could someone help me balancing this equation? I am second guessing myself that I have written the equation from the question correctly in the first place.

"Bacterial cells with an empirically determined molecular formula of C5H7NO2 are grown on a
glucose substrate with ammonia as nitrogen source. The yield of cells is determined to be
0.42 g cells/g glucose.
a. Write and balance a stoichiometric equation to describe this system
b. What is the respiratory quotient?"

The equation I think it is from the question:

C6H12O6 + NH3 = C5H7NO2 + CO2 + H20

(Glucose + Ammonia) = (Cells + Carbon dioxide + Water)

Then after I balanced it:

5C6H1206 + 6NH3 = 6C5H7NO2 + CO2 + 18H20

If anyone could help in anyway I'd be really grateful, struggling with the content in this course at the moment so any help would be appreciated.
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ChenBeier
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Re: Equation balance help

Post by ChenBeier »

The balanced equation is still wrong.
Left 30 C, 78 H, 30 O, 6 N Right 31 C 78 H, O 32 ,6 N
You forget to count the CO2

The RQ = V(CO2)/V(O2)
metalgearrex21
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Re: Equation balance help

Post by metalgearrex21 »

Oh yeah I forgot the CO2! From the question I don't think I have the equation correct to begin with though as the respiratory quotient is moles CO2 produced/moles O2 consumed.

I think I should have oxygen on the left maybe also then. And I think I might have to use this formula:

Substrate + Oxygen + Nitrogen Source →(dry) Biomass + Carbon Dioxide + Water

CwHxOyNz + aO2 + bHgOhNi = cCHaObNd + dCO2 + eH2O

I think this is why balancing it the other way isn't working out IO think but I am still confused by it :(
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ChenBeier
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Re: Equation balance help

Post by ChenBeier »

What about this

C6H12O6 + O2 + NH3 => C5H7NO2 + CO2 + 4 H2O

RQ = 1
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