Problem: The pH of 0.10 M of an unknown acid is 4.5. Calculate the Ka of the acid.a. 1.0 x 10-9b. 1.0 x 10-8c. 3.16 x 10-5d. 1.0 x 10-10e. 3.16 x 10-6

FREE Expert Solution

We’re being asked to calculate the equilibrium constant of HA if a 0.10 M solution has a pH of 4.5



Remember that weak acids partially dissociate in water and that acids donate H+ to the base (water in this case). 


The dissociation of HNO2 is as follows:

HA(aq) + H2O(l)  H3O+(aq) + A(aq)


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Problem Details

The pH of 0.10 M of an unknown acid is 4.5. Calculate the Ka of the acid.

a. 1.0 x 10-9

b. 1.0 x 10-8

c. 3.16 x 10-5

d. 1.0 x 10-10

e. 3.16 x 10-6

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