Using a less polar solvent when running a TLC will result in non polar compounds migrating a distance up the plate because of interactions between the nonpolar compound and the stationary phase and interactions between the nonpolar compound and the mobile phase.

pH = 10.9

Explanation:

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In this case, according to the given information, it turns out possible for us to say that the undergoing reaction between this buffer and OH⁻ promotes the formation of more CO₃²⁻ because it acts as the base, we can do the following:

The resulting concentrations are:

Thus, since the pKa of this buffer system is 10.2, the change in the pH would be:

Which makes sense since basic OH⁻ ions were added.

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