In: Chemistry
CH4(g) + Cl2(g) CH2Cl2(g) + 2 HCl(g) Use the data in the table below to calculate the standard enthalpy, ∆H˚, for the reaction above. Substance CH4(g) CH2Cl2(g) HCl(g) ∆Hf˚, kJ•mol-1 –74.6 –95.4 –92.3
fH0 CH4(g) = -74.6 KJ/mol
fH0 Cl2(g) = 0 KJ/mol
fH0 CH2Cl2(g) = -95.4/mol
fH0 HCl(g) = -92.3 KJ/mol
H0 = fH0 (Product) - fH0 (Reactant)
H0 = [(fH0 CH2Cl2(g) ) + (2fH0 HCl(g))] - [(fH0 CH4(g) ) + (2fH0 Cl2)]
= [ (-95.4) + (2 (-92.3)] - [(-74.6) + (0)]
= [-280] - [-74.6]
H0 = -205.4 KJ/mol
H0 for reaction = -205.4 KJ/mol