Answer:The volume of H2 = 243mL = 0.243 L
Pressure of H2 gas collected = 745 mm
Pressure of H2 dry gas = P of H2 collected - vapor pressure of water = 745- 23.78 = 721.22 mm
= 721.22mm /760mm/atm
Temperature = 25C = 25+273= 298 K
Using the ideal gas equation
PV = nRT
or PV = (mass/molar mass) RT
(721.22/760)atm x 0.243L = (mass/ 2g/mol) x 0.0821L.atm/mol.K x 298K
Thus mass of H2 formed = 0.0188 g
Explanation:
