Tutorial 8

[thushan]

Thermochemistry. Whoever has covered it, try and explain it to the rest of the group.

Skype Session opened.

[Bhootnike]

Thermochemistry. Whoever has covered it, try and explain it to the rest of the group.

Skype Session opened.

lets get onto it peeps!

[thushan]

Turnout wasn't too bad. Next week, Electrochemistry, to be presented by TBA.

[Lasercookie]

Logs:

This week was presented by Mr. Study, covers:

Thermochemistry
--Specific Heat Capacity
--Thermochemical Equations
--Solution Calorimetry
--Bomb Calorimetry
--Exam questions

[Bhootnike]

insightful tute!
Kudos to Mr. S!

[nooshnoosh95]

how did jenny get delta H for the very last question?? 0.O

[Jenny_2108]

how did jenny get delta H for the very last question?? 0.O

so from part A: we got calibration factor is 32kJ/C right?
Part B:
2H2 +O2 ----> 2H2O

So energy change in the calorimeter= 32*(23.70-23.35)=11.2kJ
0.05 mol H2 reacted 0.05 mol O2 => O2 is excess
We use number of mole of H2
Use the ratio: 2/0.05=deltaH/11.2
Delta H=-448kJ/mol

LOL I did wrong yesterday (just go to my rubbish bin and find the paper I did yesterday to figure out why I got different ans haha)
the temperature changes from 23.35 to 23.70 but yesterday I calculated from 23.35 to 27.30. My bad eyes ><

Thanks nooshnoosh95

Laseredd: can you pls fix the transcript? thanks 

Mr.Study: you didnt tell me   

[Lasercookie]

So energy change in the calorimeter= 32*(23.70-23.35)=11.2kJ
0.05 mol H2 reacted 0.05 mol O2 => O2 is excess
We use number of mole of H2
Use the ratio: 2/0.05=deltaH/11.2
Delta H=-448kJ/mol
the temperature changes from 23.35 to 23.70 but yesterday I calculated from 23.35 to 27.30. My bad eyes ><

As a result of the explosion the temperature of the calorimeter rose from 23.25°C to 23.70°C.

The question actually said 23.25 , which works out to:




?

(I probably should have actually evaluated the answer, rather than just doing the working last night too)

I'll get around to adding a note at the end of the transcript later tonight.

[Jenny_2108]

So energy change in the calorimeter= 32*(23.70-23.35)=11.2kJ
0.05 mol H2 reacted 0.05 mol O2 => O2 is excess
We use number of mole of H2
Use the ratio: 2/0.05=deltaH/11.2
Delta H=-448kJ/mol
the temperature changes from 23.35 to 23.70 but yesterday I calculated from 23.35 to 27.30. My bad eyes ><

As a result of the explosion the temperature of the calorimeter rose from 23.25°C to 23.70°C.

The question actually said 23.25 , which works out to:




?

(I probably should have actually evaluated the answer, rather than just doing the working last night too)

I'll get around to adding a note at the end of the transcript later tonight.

I hate my self now. Always see the numbers wrong. The method is still the same
You are correct, Laseredd Next time, dont trust anything I do

[nooshnoosh95]

haha i get it now
thanks guys