A student is trying to identify an unknown acid. The label on the acid bottle says 0.15 M, but the identity of the acid on the label has been obscured. The student prepares a solution by taking 50.0 mL of the acid, adding 20.0 mL of 0.050 M NaOH, and diluting the mixture to a final volume of 150.0 mL. The pH of the solution was 4.28. Calculate the Ka for this unknown acid. Show all work.

A100 kmol/h stream that is 97 mole% carbon tetrachloride (ccl4) and 3% carbon disulfide (cs2) is to be recovered from the bottom of a distillation column. the feed to the column is 16 mole% cs2 and 84% ccl4, and 2% of the ccl4 entering the column is contained in the overhead stream leaving the top of the column. calculate the mass and mole fractions of ccl4 in the overhead stream, and determine the molar flow rates of ccl4 and cs2 in the overhead and feed streams. 12. mw_ccla- 153.82; mw_cs2-76.14.