Given that the standard enthalpy of combustion of C _ ( S ) and CS ₂( l ) are -393.3 and -1108.76 ~kJ / mol respectively and the standard enthalpy of formation of CS ₂ is 128.02 ~kJ / mol . What is H_f^0 of SO ₂ ?

Step-by-step solution

The combustion reactions are given as follows: 1. C _ ( s ) + O _ 2( g ) CO _ 2( g ) , H₁ = -393.3 kJ/mol 2. CS _ 2( l ) + 3 O _ 2( g ) CO _ 2( g ) + 2 SO _ 2( g ) , H₂ = -1108.76 kJ/mol The enthalpy of formation of CS _ 2( l ) is given by the reaction: 3. C _ ( s ) + 2 S _ ( s ) CS _ 2( l ) , H_f^0( CS ₂) = 128.02 kJ/mol The enthalpy of combustion of CS _ 2( l ) can be expressed in terms of enthalpies of formation: H₂ = [ H_f^0( CO ₂) + 2 H_f^0( SO ₂)] - [ H_f^0( CS ₂) + 3 H_f^0( O ₂)] Since H_f^0( CO ₂) = H₁ = -3