Please explain the differences between exothermic and endothermic reactions, and include the criteria you used to distinguish between them. Additionally, please provide a real-world example to illustrate your explanation.

Ex other mic reactions are those that release energy in the form of heat or light . This is because the bonds between the react ants are we aker than the bonds between the products . End other mic reactions , on the other hand , absorb energy from their surroundings . This is because the bonds between the products are stronger than the bonds between the react ants . \n \n To distinguish between ex other mic and end other mic reactions , we can look at the change in ent hal py ( Δ H ) of the reaction . If Δ H is negative , the reaction is ex other mic . If Δ H is positive , the reaction is end other mic . If Δ H is zero , the reaction is neither ex other mic nor end other mic . \n \n A real - world example of an ex other mic reaction is the burning of meth ane gas ( CH 4 ) in air ( O 2 ): \n \n CH 4 + 2 O 2 → CO 2 + 2 H 2 O \n \n This reaction releases a large amount of heat , which is why it is often used as a source of energy in homes and industries . The bonds between the products ( CO 2 and H 2 O ) are stronger than the bonds between the react ants ( CH 4 and O 2 ), which makes the reaction ex other mic . </s>