Respuesta :
Answer:
There is 89.9 kJ of heat evolved in the combustion
Explanation:
Step 1: Data given
Mole fraction of CH4 = 0.830
Mole fraction of C2H6 = 0.112
Mole fraction of C3H8 = 0.058
Volume = 2.15 L
Temperature = 24.5 °C = 297.65 Kelvin
744 mmHg is burned
The combustion of methane (CH4) releases 891 kJ of energy
The combustion of ethane (C2H6) releases 1561 kJ of energy
The combustion of propane (C3H8) releases 2220 kJ of energy
Step 2: Calculate number of moles of
p*V= n*R*T
⇒ p = The pressure = 744 mmHg = 744/760 = 0.979 atm
⇒ V = the volume = 2.15 L
⇒ n= The number of moles = TO BE DETERMINED
⇒ R = the gas constant = 0.08206 L*atm/k*mol
⇒ T = The temperature = 24.5 °C = 297.65 Kelvin
n(total) = PV / RT = (0.979 *2.15 ) / (0.08206 * 297.65 )
n(total) = 0.0862 moles
Step 3: Calculate energy for combustion of each gas
CH4: 0.0862 moles * 0.830 * 891 kJ/mol = 63.7 kJ
C2H6: 0.0862 moles * 0.112 * 1561 kJ/mol = 15.07 kJ
C3H8: 0.0862 moles * 0.0580 * 2220 kJ/mol = 11.1 kJ
Step 4: Calculate tot heat for the combustion
63.7 kJ + 15.07 kJ + 11.1 kJ = 89.9 kJ total
There is 89.9 kJ of heat evolved in the combustion
