Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

If the pKa for an indicator is 3.4, for which of the following titrations would

ID: 938166 • Letter: I

Question

If the pKa for an indicator is 3.4, for which of the following titrations would it be appropriate asan indicator for the equivalence point?

borwh gtitation 6. If the pKa for an indicator is 3.4, for which of the following titrations would it be appropriate as an indicator for the equivalence point? A) B) C) D) HNOs titrated with strong base HC2H302 titrated with strong base C2HsNH2 titrated with strong acid C6HsNH2 titrated with strong acid Ka & Kb values HNO2 HCN HC2H302 NH3 C6H5NH2 C2HsNH2 4.0 x 104 6.2 x 10-10 1.8 x 10-5 1.8 x 105 3.8 x 1010 5.6 x 104

Explanation / Answer

if pKA = 3.4

then

this means that; approx:

Ka = 10^-pKa = 10^-3.4 = 3.9810 *10^-4

then choose anything near that

choose HNO2 since it is the only acid with the nearest pKa value

it must be titrated with a STRONG base, so choose A