Nitromethane (CH3NO2) burns in air to produce significant amounts of heat. 4 CH3NO2 (l) + 3 O2 (g) → 4 CO2 (g) + 6 H2O (l) + 2 N2 (g) , ΔHorxn = -2836 kJ If 1,273 kJ of heat are produced from the burning of nitromethane, how many grams of nitromethane were burned?

There are two steps in the usual industrial preparation of acrylic acid, the immediate precursor of several useful plastics. in the first step, calcium carbide and water react to form acetylene and calcium hydroxide: cac2 (s) + 2h2o (g) → c2h2 (g) + caoh2 (s) =δh−414.kj in the second step, acetylene, carbon dioxide and water react to form acrylic acid: 6c2h2 (g) + 3co2 (g) + 4h2o (g) → 5ch2chco2h (g) =δh132.kj calculate the net change in enthalpy for the formation of one mole of acrylic acid from calcium carbide, water and carbon dioxide from these reactions. round your answer to the nearest kj .