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Topic: Calculating "heat involved per mole of NaOH"  (Read 9346 times)

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Offline aeromat2

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Calculating "heat involved per mole of NaOH"
« on: December 15, 2010, 08:05:47 PM »
We are doing a series of lab experiments throughout our Chemistry class and one of them was called "Heats of Reaction". Reaction 1 [below] was to add 200mL of cool tap water and react it with approx 2.04g of NaOH. We swirl the flask and keep record of initial and final temperatures.

One question that I am having problems with was this:

f) the total amount of heat involved per mole of NaOH?

(I don't know how to calculate this, or where to even start.)

Known information:

Change in temp: 1.8 celsius
mass of NaOH: 2.04g
Molar mass of NaOH: 47g/mol
mol of NaOH: 0.0434 mol
empty flask mass: 95.75g

Amount of heat absorbed by solution [NaOH + water]: 0.0154 KJ
Amount of heat absorbed by flask [using flask mass to calculate]: 0.721 KJ

Offline Borek

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Re: Calculating "heat involved per mole of NaOH"
« Reply #1 on: December 16, 2010, 04:16:34 AM »
It is a simple ratio. You know amount of heat evolved when 0.0434 mol of NaOH dissolved, how many times more heat would evolve in the case of 1 mole?
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