Calculate the heat of formation of carbon dioxide CO2 (g), based on thermochemical equations: H2 (g) + 0,5O2 (g) = H2O (g), ∆H = -285,84 kJ; CH4 (g) + 2O2 (g) = 2H2O (liq) + CO2 (g), ∆H = -890.31 kJ; C (s) + 2H2 (g) = CH4 (g), ∆H = -74.68 kJ