What is the pressure of the neon gas?

Question

A student has stored 100.0 mL of neon gas over water on a day when the temperature is 27 °C. The barometer in the room reads 99.10 kPa. What is the pressure of the neon gas?

Answer 1

Hi Sydney:

The key is to know what the pressure of water is at 27 deg C. So this is a Daltons law problem which is:

Ptotal = P(neon) + P(water)

so from a table at 27 deg C the vapor pressure of water is 3560 Pa or 3.56 kPa

99.10 kPa = P(neon) + 3.56 Kpa

solve for P(neon) = 95.5 Kpa