A sample of hydrogen is collected over water at 25∘C in a 250.0mL flask. The barometric pressure is 755mmHg, and the vapor pressure of water at 25∘C is 24mmHg. What amount of hydrogen, in moles, is present in the flask?
a) 1.02×10−2mol
b) 1.05×10−2mol
c) 9.8×10−3mol
d) 1.15×10−2mol