The ethoxide ion, C₂H₅O^-, is a strong base. It is similar to hydroxide, OH^-, but with the hydrogen atom in hydroxide replaced by the C₂H₅ group. When mixed with water, the salt sodium ethoxide will react with H₂O to make C₂H₅OH, ethyl alcohol, and OH^-(aq) ions. An unknown mass of NaC₂H₅O was slowly added to 20.0 mL water, and the resulting solution was titrated with 1.815 M HCl solution. A total of 41.5 mL of acid was needed to neutralize the resulting solution.

(a) Write the net ionic reaction between sodium ethoxide and water.

(b) Would you expect the reaction between ethoxide ions and water to be exothermic or endothermic? Explain your answer.

(c) What mass of NaC₂H₅O was added to the water originally?

(d) At the endpoint, the system consists of two volatile liquids, water and ethanol. What is the expected equilibrium vapor pressure of this solution at 25.0 °C? P°(H₂O) = 23.77 torr; P°(C₂H₅OH) = 59.02 torr.

(e) Can fractional distillation be used to separate any of the ethanol from the water?

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