CHEM 272 Lecture Notes - Lecture 4: Ammonia, Equivalence Point, Titration

• School: University of Maryland
• Department: Chemistry and Biochemistry
• Course: CHEM 272
• Professor: julin

Document Summary

Discussion lab 4a: co2 (g) + h2o h2co3 hco3- + h+ dh2o is slightly acidic because interaction with the atmosphere allows co2 to dissolve into it. Since there are no natural buffers present in h2o regulating its ph, dh2o may have a slightly lower ph than neutral: a method for removing co2 from dh2o would be to boil the water in a closed system. Because co2 has a higher boiling point than h2o, solubility decreases and dissolved co2 in h2o decreases. In experiment 4b, co2 is displaced by n2: the equivalence point is when the moles of acid = moles of base added, or when all acid is converted to its conjugate base. The endpoint is after the equivalence point when the indictor changes color, when the titration is finished. This experiment measured endpoint because we titrated until the solution turned a pale pink.