A Sample of Hydrogen Gas Was Collected by Displacement of Water

Multiple Choice

A sample of hydrogen gas was collected by displacement of water in a large gas buret. The total pressure in the buret was measured as 764.2 torr, the temperature was 23.0 °C, and the buret contained 511 mL of the collected gas. How many moles of hydrogen were collected?(At 23.0 °C, the vapor pressure of water is 21.1 torr.)

A) 0.0191 moles
B) 0.0206 moles
C) 0.0211 moles
D) 0.0215 moles
E) 0.0217 moles