Calculate the quotient [co32–]/[hco3–] at ph 10.75.

The chemical equation is:

HCO3^    ->  H^+ + CO3^2- 

We know that the formula for Ka is:
Ka = [H^+][CO3^2-]/[HCO3^-] 

log Ka = log[H^+] + log[CO3^2-]/[HCO3^-] 
pKa = pH - log[CO3^2-]/[HCO3^-] 
log[CO3^2-]/[HCO3^-] = pH - pKa = 10.75 - 10.329 = 0.421 
[CO3^2-]/[HCO3^-] = Antilog (0.421)  = 2.636 

2.636

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

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