Answer Happy

C) After 40.0mL of NaOH were added. First, determine how much excess NaOH is present and then determine the total volume of solution FALL 2021 CHEM 104 39) A student decided to determine the molar mass of an unknown diprotic acid (HA). After standardizing her base (-0.1M NaOH) with KHP she determined the amount of NaOH needed to reach the equivalence point. Use her data to (a) determine the actual molarity of the base and (b) determine the molar mass of the diprotic acid. a) Molarity of NaOH (use the diagram if you need guidance) MM of KMP. 20422g/mol KHP sedi 0.4929 (NAOH): 10mL V (NAOH) 31.12mL NON-CR30 b) Molar mass of the dipotic acid (no diagram, use the cquation below). H2A + 2NaOH-NaA + 2H20 mass HAI 0.2059 M (NaOH). M from a) V. (NAOH): 14.10mL V (NAOH): 46.44ml 40) You have a 1.00M solution of an unknown weak acid (ILA) where K. 1.5x10- and Ke-6.0x10! a) Write the equilibrium equation for K.. b) Write the equilibrium equation for c) Determine the pH of the solution and explain why you do not need to consider the generated in the second equation d) Determine the concentration of the A-ion in the solution. Beware, you will need to me the result of the first equilibrium in the wond equilibrium! 41) Predict the sign of AH. AS and As... AH.. S. AS Boiling water Freezing water Throwing sodium metal in water 42) Given the values of AH and As, which of the following changes will be spontaneous at constant Tandp AH (kJ/mol +25 Spontaneous? AS (J/molxK) -5.0 -100 40 T(K) 300 300 200 -10