How Does Heat Release Affect Water Temperature in Thermochemical Reactions?

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The discussion centers on a thermochemical reaction that releases 90 kJ of heat, and the challenge is to determine the final temperature of 100 g of water initially at 20 degrees Celsius. The participant uses the equation q = mc(delta T) but mistakenly inputs 400 kJ instead of the correct 90 kJ for q. Additionally, there is confusion regarding the specific heat capacity, where the correct unit should be J/(g K) instead of J/(mol deg C). Clarifications are provided on these points, emphasizing the importance of accurate unit conversion and correct values in calculations. Understanding these concepts is crucial for solving thermodynamics problems effectively.
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I know this is a physics forum, but this problem is mainly physics, and exceedingly simple:

Homework Statement



A certain reaction releases about 90 kJ of heat when stoichiometric amounts of reactants react. If the reaction goes to completion in 100 g of water whose initial temperature is 20 deg C, what is the final temperature of the water?


Homework Equations



q = mc(delta T), I believe, so delta T = q / (mc)

The Attempt at a Solution



I don't know what I'm doing wrong, but if I plug the 400 kJ = 400000 J into q and the 100 g mass into m and 4.184 J / (mol deg C) into c, I get an insane change in temperature around 215 degrees. I am obviously forgetting some step or misunderstanding something... I've always had trouble with thermodynamics stuff like this. Any help would be greatly appreciated.. thank you!
 
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Firstly should q not be 90kJ. Secondly the units of c that you provide are J/(g K). Other than that your calculations seem fine.
 
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