Question

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

Answer 1

To calculate the quotient [CO32–]/[HCO3–] at pH 10.75, we need to know the concentrations of carbonate ion (CO32–) and bicarbonate ion (HCO3–). The question does not provide this information. However, we can calculate the concentrations of these ions using the ionization equilibrium of carbonic acid (H2CO3).

Step-by-step explanation:

To calculate the quotient [CO32-]/[HCO3-] at pH 10.75, we need to know the concentrations of carbonate ion (CO32-) and bicarbonate ion (HCO3-). Unfortunately, the question does not provide this information. However, we can calculate the concentration of these ions using the ionization equilibrium of carbonic acid (H2CO3). At pH 10.75, we need to consider the following equilibrium reactions:

H2CO3 ⟷ HCO3- + H3O+

HCO3- ⟷ CO32- + H+

From these equilibrium reactions, we can calculate the concentrations of CO32- and HCO3- using the provided information on the equilibrium constants of these reactions and the total concentration of carbonic acid.

Answer 2

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

Answer:

2.636