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Enthalpy change help!

I'm stuck on a question to do with enthalpy change:

Student Initial Temp Highest Temp
1 17.0 22.0
2 18.0 21.0
3 17.5 23.5
4 16.5 21.5
5 16.0 22.0

"The students watched to calaculate the enthalpy change of the reaction.
Calculate the average temperature rise that they should use."

Do I find the mean of the 'initital temp' and mean of the 'highest temp' then subtract them? or do I do 23.5-17.5 becuase they're the highest values of the lot?

Reply 1

Kaeroll

I'd use the averages.

Reply 2

crazylady_012

Do highest - initial of each student, i.e. 1 22-17 = 5, 2 21-18 =3and put in a new column. Then find the mean of the column. The students would use that average temperature rise.

Are you cheating?

it's an exam question, I didn't actually do the experiment :P

anyone else?

You find the temp change for each i.e. final temp-initial (for all values) and then find the mean of these changes in temp.

so:

22.0 -17.0 =
21.0 -18.0 =
etc etc.

Then with the values of temperature change, add them up and find the mean.