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Determine the value of K for the reaction formed when the two given reactions are added together. CO2(aq) + H2O(l) ⇌ (aq) + H+(aq) K1 = 4.5 × 10−7 (aq) ⇌ H+(aq) + (aq) K2 = 4.7 × 10−11 _________________________________________________________________________________________________ CO2(aq) + H2O(l) ⇌ 2H+(aq) + (aq) K3 = ?

Calculate pPb2+ at the equivalence point when 25.00 mL of 0.120 M  is titrated with 0.120 M Pb2+. Ksp = 7.4 × 10−14 for PbCO3.

You need to prepare 1.00 L of a pH 5.00 propionic acid buffer with a total concentration of 50 mM. Calculate the millimoles of propionic acid and sodium propionate needed to prepare the buffer. Ka = 1.34 × 10−5 for propionic acid. Hint: Set millimoles of propionate equal to x and millimoles of propionic acid equal to 50 − x. Insert into the Henderson-Hasselbalch equation and solve for x. X mmol sodium propionate; Y mmol propionic acid (Report 1 decimal place) Answer setup:  X; Y

For the following set of replicate measurements calculate the : (Report to 2 decimal places) Average deviation [A], [B], [C], [D], [E], [F]

Calculate the pH of a 0.033 M Na2SO3 solution. pK1 = 1.66 and pK2 = 6.85 for sulfurous acid.

All of the following are strong acids, EXCEPT

A NaOH solution is standardized using the monoprotic primary standard potassium hydrogen phthalate, KHP (FM 204.22). If 0.698 6 g of KHP requires 43.92 mL of NaOH, what is the NaOH concentration?

___________ expresses the margin of uncertainty associated with a measurement.

Calculate the pH of water at 50°C. Kw = 5.31 × 10−14 at 50°C.

Three different bottles of vinegar were analyzed by the same analyst for percentage acetic acid content. The following results were obtained. Bottle no.1 Bottle no. 2 Bottle no.3 3.88 5.72 [K] 3.92 5.61 [L] 3.75 5.60 [M] 3.84 5.68 [N] 3.91 5.66 [O] How many measurements of sample 3 would have to be taken to reduce the 90% C.I. to 0.0750 ppm? (report 3 decimal places)