A student collects 47.56 mL of hydrogen gas over water at a temperature of 22C. The atmospheric pressure is reported to be 29.78 inHg. a. what is atmospheric pressure in Hg? b. what is vapor pressure of water in 22C? c. what is the pressure of dry H2 in mmHg? In atm? d. Assuiming ideal gas behavior, how many moles of H2 has were collected?