Question

A mixture of helium and neon gases is collected over water at 28.0°C and 745 mmHg. If the partial pressure of helium is 368 mmHg, what is the partial of neon? (Vapor pressure of water at 28oC = 28.3 mmHg)

Answer 1

$P_{Total} = 745 \;mmHg$

$P_{He} = 368 \; mmHg$

$P_{H_2O} = 28.3 \;mmHg$

$P_{Total} = P_{Ne} + P_{He} + P_{H_2O}$

$P_{Ne} = P_{Total} - P_{He} - P_{H_2O}$

$P_{Ne} = 745 - 368 - 28.3 = 348.7 \;mmHg$