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URGENT chem question help bond enthalpies

Hi, please could i have help on this question? I understand why statements 1 and 2 are correct but i don’t get why 3 is correct? If the reaction is exothermic, surely the enthalpy of products should be greater so when you subtract the enthalpy of the reactants from the products, you get a negative number which means it s exothermic?
Here is the question: https://app.gemoo.com/share/image-annotation/614490829553283072?codeId=MlQwqlp9VqKJY&origin=imageurlgenerator

Thank you so much!
Reply 1
Original post by anonymous294
Hi, please could i have help on this question? I understand why statements 1 and 2 are correct but i don’t get why 3 is correct? If the reaction is exothermic, surely the enthalpy of products should be greater so when you subtract the enthalpy of the reactants from the products, you get a negative number which means it s exothermic?
Here is the question: https://app.gemoo.com/share/image-annotation/614490829553283072?codeId=MlQwqlp9VqKJY&origin=imageurlgenerator

Thank you so much!

If you draw an energy/enthalpy diagram for an exothermic reaction, you'll see that the enthalpy of the products is less than that of the reactants. This means that energy is lost from the system given out as heat.
enthalpy of products - enthalpy of reactants
The enthalpy has decreased, hence the negative value for ΔH.
https://www.chemguide.co.uk/physical/energetics/basic.html
Reply 2
Original post by bl0bf1sh
If you draw an energy/enthalpy diagram for an exothermic reaction, you'll see that the enthalpy of the products is less than that of the reactants. This means that energy is lost from the system given out as heat.
enthalpy of products - enthalpy of reactants
The enthalpy has decreased, hence the negative value for ΔH.
https://www.chemguide.co.uk/physical/energetics/basic.html

Ohhh ok thank you!!

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