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Sure, here's a problem for a chemistry student to solve:Calculate the acid dissociation constant (Ka) of a 0.1 M solution of acetic acid, given its pH is 3.7. The pKa value of acetic acid is 4.74.

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To calculate the acid dissociation constant  Ka  of a 0.1 M solution of acetic acid, we can use the following steps:1. Convert the pKa value to Ka:pKa = -log Ka 4.74 = -log Ka Ka = 10^-4.74 Ka  1.8 x 10^-5 2. Calculate the concentration of H+ ions using the given pH value:pH = -log [H+] 3.7 = -log [H+] [H+] = 10^-3.7 [H+]  2.0 x 10^-4  M3. Use the Ka expression to find the concentration of acetate ions  A- :Ka = [H+][A-]/[HA]1.8 x 10^-5  =  2.0 x 10^-4   A- / 0.1 - A- 4. Solve for A-:A-  9.0 x 10^-4  M5. Calculate the concentration of undissociated acetic acid  HA  remaining in the solution:[HA] = 0.1 M - A-[HA]  0.1 - 9.0 x 10^-4 [HA]  0.0991 M6. Verify the Ka value using the calculated concentrations of H+, A-, and HA:Ka = [H+][A-]/[HA]Ka   2.0 x 10^-4   9.0 x 10^-4  / 0.0991 Ka  1.8 x 10^-5 The acid dissociation constant  Ka  of the 0.1 M solution of acetic acid is approximately 1.8 x 10^-5 .
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