I believe you have made a typo in the final equation. I don't think you can obtain equation 3 from 1 and 2. If you intended to write
CH4 + 2Cl2 ==> CH2Cl2 + 2HCl, then just add equation 1 to equation 2.
Use Hess's law and the reactions
1) CH 4(g)+ Cl 2 (g)--->CH 3 CL(g) + HCl (g)
2) CH 3 Cl (g) + Cl 2 (g)---> CH 2 Cl 2 (g) + HCl (g)
to determine the enthalpy for the reaction
CH4 (g) + 2CH 2 (g)---> CH2 Cl 2 (g) + 2HCl (g)?
1 answer