Skip to main content

CH4(g) + 2O2(g) -> CO2(g) + 2H2O(g) Why is this reaction classified as exothermic?

Based on the energy requirements or generation, reactions can be classified as either endothermic or exothermic. The reactions which need energy to proceed are known as endothermic reactions. The reactions in which energy is released are known as exothermic reactions. In other words, energy is supplied to endothermic reactions and is obtained from exothermic reactions. 


The given reaction is: 


`CH_4 (g) + 2O_2 (g) -> CO_2 (g) + 2H_2O (g)`


Here, methane reacts with oxygen...

Based on the energy requirements or generation, reactions can be classified as either endothermic or exothermic. The reactions which need energy to proceed are known as endothermic reactions. The reactions in which energy is released are known as exothermic reactions. In other words, energy is supplied to endothermic reactions and is obtained from exothermic reactions. 


The given reaction is: 


`CH_4 (g) + 2O_2 (g) -> CO_2 (g) + 2H_2O (g)`


Here, methane reacts with oxygen to generate carbon dioxide and water. 


The binding energy of a molecule is defined as the difference between energy of that molecule and its elements (in their ground state). The binding energy of the various species used in this reaction are:


methane: -75 kJ/mol


oxygen: 0 


carbon dioxide: -394 kJ/mol


water: -242 kJ/mol


Thus, we can see that the formation of products will release more energy than reactants. We can also calculate the energy change when this reaction takes place.


Energy change = binding energy of products - binding energy of reactants


= -394 + 2 x (-242) - (-75) + 2 x 0 = -803 kJ/mol


negative sign indicates that the energy is released. 


Thus, this reaction is exothermic and generates 803 kJ of energy per mole.


Hope this helps. 

Comments

Post a Comment

Popular posts from this blog

What is the meaning of "juggling fiends" in Macbeth?

Macbeth is beginning to realize that the three witches have been deceiving him since he first encountered them. Like jugglers, they have kept changing their forecasts in order create confusion. This is particularly apparent when the Second Apparition they raise in Act IV,   Scene 1 tells him that no man of woman born can overcome him in hand-to-hand battle--and then Macbeth finds himself confronted by the one man he has been avoiding out of a... Macbeth is beginning to realize that the three witches have been deceiving him since he first encountered them. Like jugglers, they have kept changing their forecasts in order create confusion. This is particularly apparent when the Second Apparition they raise in Act IV,   Scene 1 tells him that no man of woman born can overcome him in hand-to-hand battle--and then Macbeth finds himself confronted by the one man he has been avoiding out of a sense of guilt, and that man tells him: Despair thy charm. And let the angel whom thou still hast serve...
Post a Comment
Read more

In Martel's Life of Pi, how does writing a diary help Pi Patel build on his leadership skills?

At the end of chapter 73, Pi first divulges the fact that he had started a diary after about a week alone at sea. Pi claims that he wrote about "practical stuff" (208) such as what he caught for food, foreseeable problems and solutions, Richard Parker, and reflections about specific events that occurred. In a sense, Pi is the captain of his ship; therefore, he must take responsibility for himself and his crew. He can... At the end of chapter 73, Pi first divulges the fact that he had started a diary after about a week alone at sea. Pi claims that he wrote about "practical stuff" (208) such as what he caught for food, foreseeable problems and solutions, Richard Parker, and reflections about specific events that occurred. In a sense, Pi is the captain of his ship; therefore, he must take responsibility for himself and his crew. He can do this by writing down events, problems and solutions, and reflections to look back on when confronted with repeated problems. It can ...
Post a Comment
Read more

Why did Tybalt attack and kill Mercutio instead of Romeo, who he had originally been targeting?

Though Tybalt's quarrel is with Romeo, he begins the momentous duel in Act 3 by fighting with and killing Mercutio instead. Tybalt ultimately attacks Mercutio because the garrulous and hot-headed character insults Tybalt and goads him into a duel to protect Romeo's honor. From the beginning of the encounter in Act 3, Scene 1, it's clear that Mercutio is itching for a fight. For instance, when Tybalt signals that he wants to talk to Mercutio... Though Tybalt's quarrel is with Romeo, he begins the momentous duel in Act 3 by fighting with and killing Mercutio instead. Tybalt ultimately attacks Mercutio because the garrulous and hot-headed character insults Tybalt and goads him into a duel to protect Romeo's honor. From the beginning of the encounter in Act 3, Scene 1, it's clear that Mercutio is itching for a fight. For instance, when Tybalt signals that he wants to talk to Mercutio and Benvolio, Mercutio responds "And but one word with one of us?/ Couple it w...
Post a Comment
Read more