Part A The heat of combustion of CH4 is 890.4 kJ/mol and the heat capacity of H2
ID: 1086380 • Letter: P
Question
Part A The heat of combustion of CH4 is 890.4 kJ/mol and the heat capacity of H2O is 75.2 J/mol × K Find the volume of methane measured at 298 K and 1.97 atm required to convert 0.840 L of water at 298 K to water vapor at 373 K Express your answer with the appropriate units. V-1 Value Units - Part A Propane has a normal boiling point of -42.0° C and a heat of vaporaonAHaof 19.04 kJ/mol What is the vapor pressure of propane at 40.0 C? Express the pressure in torrs to three significant figures. torr Constants | Periodic Table Part A sealed flask contains 0.40 g of water at 28 °C. The vapor ressure of water at this temperature is 28.36 mmHg What is the minimum volume of the flask in order that no liquid water be present in the flask? Express your answer using two significant figures. ou may want to reference (Pages 478-487) Section 11.5 hile completing this problem.Explanation / Answer
Part A :
Hvap = 2257000 J/kg.K
Molar mass of H2O = 18
Molar mass of CH4 = 16
(H2O) = 1000 kg/m^3 = 1 kg/l
mass H2O
m = *V = 1 kg/l*0.840 l
m = 0.840 kg
Q = m*[c*T+Hvap]
Q = 0.840kg *[(75.2/18 JK-1) * (373 - 298)K + 2257000 Jkg-1]
Q = 1896.14kJ
Mass of CH4
n(CH4) = Q / H combustion of (CH4)
n(CH4) =1896.44.14 kJ / 890.4 kJmol-1
n(CH4) = 2.129 mol
Now , Volume of Methane,
PV = nRT
Or, V = nRT/P
V = 2.129*0.082*298 / 1.97
V = 26.40 L