Answer:
The correct answer is 62.5 %.
Explanation:
Based on the given information, the partial pressure of butyl butyrate is 50 mmHg and the partial pressure of water is 710 mmHg.
Hence, the total pressure is 710+50 = 760 mmHg
According to Dalton's law of partial pressure,
Partial pressure = mole fraction * total pressure
Mole fraction of water is,
Partial pressure of water/Total pressure = 710/760 = 0.93
Similarly, the mole fraction of butyl butyrate is,
Partial pressure of butyl-butyrate/Total pressure = 50/760 = 0.07
Therefore, mole% of water is 0.93 * 100 = 93 %
For calculating mass%,
Mass of H2O = 0.93 * 18 = 16.8 grams (The molecular mass of water is 18 grams per mole)
The molecular mass of butyl-butyrate is 144 gram per mole
The mass of butyl-butyrate = 144 * 0.07 = 10.08 grams
The mass percent of water will be,
Mass % of water/Total mass % * 100 = 16.8 / 10.08 + 16.8 * 100 = 62.5%.
