Base your answers to questions 77 and 80 on the information below and on your knowledge of chemistry.
A company produces a colorless vinegar that is 5.0% HC2H3O2 in water. Using thymol blue as an indicator, a student titrates a 15.0-milliliter sample of the vinegar with 43.1 milliliters of a 0.30 M NaOH(aq) solution until the acid is neutralized.
77 Based on Table M, what is the color of the indicator in the vinegar solution before any base is added? [1]
78 Identify the negative ion in the NaOH(aq) used in this titration. [1]
Answer--> OH- or hydroxide. |
79 The concentration of the base used in this titration is expressed to what number of significant figures? [1]
80 Determine the molarity of the HC2H3O2 in the vinegar sample, using the titration data. [1]