Answer:
reaction 2 involves a greater change in energy
Step-by-step explanation:
(1) CH4 + 2 O2 → CO2 + 2 H2O + 890 kJ
(2) C3H8 + 5 O2 → 3 CO2 + 4 H2O + 2,220 kJ
The two reactions are exothermic as they are both combustion reactions.They both involve a change in energy. The first, 890KJ was released and in the second reaction 2220KJ of energy was released.
From the heat released from both reaction, there is a greater change in energy in reaction 2 because 2220KJ is greater than 890KJ.