[Embryopirate]

Hello, I've been trying to calculate what my pH should be under 5% and 6% CO2 gas in an incubator at 39°C.

The media is PZM3, and is mainly bicarbonate buffered.

NaCl                   (108 mM)
KCl                     (10 mM)
KH2PO4              (.35 mM)
MgSO4·7H2O      (.40 mM)
NaHCO3              (25.07 mM)
Na-pyruvate        (.2 mM)
Ca-(lactate)2·5H2O (2 mM)
L-Glutamine          (1 mM)
Hypotaurine          (5 mM)
Basal Medium Eagle amino acids
Minimum Essential Medium nonessential amino acids
Gentamicin
Fatty acid-free BSA

The media should be around 7.3 at 5%, but I've been struggling to prove this with the henderson-hasselbalch equation and ideal gas law equations. I'm also at sea level.

I've seen the pKa used for HCO3 and CO2 to be 6.1, but I must be doing the rest wrong since I'm getting 8.4 I would greatly appreciate some help with this and figuring out the difference in pH at 5% and 6% CO2.

Thank you in advance, and sorry for formatting

[AWK]

H-H simplified method for such a complex mixture is rather not applicable.

[Embryopirate]

H-H simplified method for such a complex mixture is rather not applicable.

oh man... that explains one reason I'm having so much trouble. If only my major professor would take that as an answer 

From what I've gathered, it's mainly for my buffers like sodium bicarbonate. Which would be my conjugate acid, and the conjugate base would be carbon dioxide.
pH = 6.1 + log(HCO3 / (0.03 * PaCO2))
Is this applicable for my buffers? and CO2 in solution?

[AWK]

It is not possible to calculate the exact pH of the buffer without knowing exactly the concentration of all the ingredients. The formula you are trying to apply is a modified H-H equation adapted to blood pH (you only need to correctly insert pCO2 in mmHg).
A pH of about 5.5-6.0 can be expected with the medium composition given unless the amino acid mixtures added are buffered.