Please provide the steps.
The acid dissociation constant for a weak acid is determined to by 5.883 x 10-4 (± 0.02%). What is the pKa of the acid?
pKa = -log Ka = -log (5.883E-4 +/- 0.0002
s = +/- 0.434 x (0.0002E-4/5.883E-4) = +/- 0.01475, then
pKa = -log(5.883E-4) +/- 0.01475
pKa = +3.230 +/- 0.01475
In line 2 I would round that to 0.0148 and use that in line 4
Thank you!
To find the pKa of an acid using its acid dissociation constant, you need to take the negative logarithm base 10 of the acid dissociation constant (Ka). Here are the steps to calculate the pKa:
Step 1: Identify the given values:
- Acid dissociation constant (Ka) = 5.883 x 10^(-4) (± 0.02%)
Step 2: Calculate the pKa:
pKa = -log10(Ka)
Step 3: Substitute the value of Ka into the equation:
pKa = -log10(5.883 x 10^(-4))
Step 4: Simplify the equation:
pKa = -log10(5.883) - log10(10^(-4))
Step 5: Evaluate the logarithms using a calculator:
pKa ≈ -(-3.230) - (-4)
Step 6: Perform the subtraction and simplify:
pKa ≈ 3.230 + 4
pKa ≈ 7.230
Therefore, the pKa of the acid is approximately 7.230.