Which reaction is endothermic? 2brcl mc019-1.jpg br2 + cl2 + 29.3 kj 2h2 + o2 mc019-2.jpg 2h2o + 572 kj c + o2 mc019-3.jpg co2 + 394 kj n2o4 + 59 kj mc019-4.jpg 2no2

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Which reaction is endothermic? 
a) 2BrCl mc019-1.jpg Br2 + Cl2 + 29.3 kJ 
b) 2H2 + O2 mc019-2.jpg 2H2O + 572 kJ 
c) C + O2 mc019-3.jpg CO2 + 394 kJ 
d) N2O4 + 59 kJ mc019-4.jpg 2NO2

If so, the answer would be letter D. 
when you say endothermic reaction, heat is absorbed, heat is released in exothermic.

Only one reactant yields 2 or more products. meaning you will only have 1 product and it will break down into 2 or more products. eg. h2o -> h2 + o2