Given the following data:
(1) 2 h2(g) co2(g) ch4(g) o2(g) dgorxn = 343 kj
(2) 2 h2(g) o2(g) 2 h2o(l) dgorxn = -474 kj
calculate δgorxn (kj) for
(3) ch4(g) 3 o2(g) 2 h2(g) co2(g) 4 h2o(l) δgorxn =?