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Consider the reaction pathway graph below.

Which kind of reaction does this graph represent?
A. exothermic because Hrxn = –167 kJ
B. exothermic because Hrxn = 167 kJ
C. endothermic because Hrxn = –1,083 kJ
D. endothermic because Hrxn = 1,083 kJ

Consider the reaction pathway graph below. Which kind of reaction does this graph-example-1
User Papacostas
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2 Answers

3 votes

Answer:

A

Step-by-step explanation:

the graph shows reactants that have more energy than the products and when you find Hrxm you get -167. Also exothermic reactions are always negative and not positive

User Jerlam
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6 votes
Hello!

The reaction that the graph represents is A. Exothermic because Hrxn=-167 kJ

To calculate Hrxn we apply the following equation:


Hrxn=Hproducts-Hreagents=-625kJ-(-458kJ)=-167kJ

Looking at the graph, and at the result of the calculations, we can see that the enthalpy of the products is lower than the enthalpy of the reagents, because the sign is negative. That means that the reaction releases energy in the form of heat and that the reaction is exothermic.

Have a nice day!
User Singh Arjun
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