Conclusion:
Tuesday, April 29, 2014
Thursday, April 24, 2014
Tuesday, April 22, 2014
Combustion of a Candle Lab
Purpose:
To observe a burning candle and calculate the heat associated with the combustion reaction.
Procedure:
1) Measure and record the length of a candle in centimeters.
2) Place the candle on a small piece of aluminum foil and measure the mass of the foil-candle system.
3) Note the time as you light the candle. Let the candle burn for about five minutes.
4) Extinguish the candle and record the time.
5) Measure the mass of the foil-candle system again.
Data:
Analyze and Conclude:
1) 
2) The wick is the one that is burning.
3) The wax is there to hold the wick in place.
4) The air on top of the candle is hotter because heat rises.
5) The candle lost 1.2 centimeters and lost .3 grams. For length it would be mostly the wax and for mass it would be the wick.
6) The wick acts as towel and soaks up the wax. Then the wax and wick burn.
7) C20 H42 30 1/2 O2 ---> 20CO2 + 21H2O
8) 1.16g (1mol/282g) = .00411348 mol
Monday, April 21, 2014
Friday, April 18, 2014
Thursday, April 17, 2014
Tuesday, April 8, 2014
Thursday, April 3, 2014
Heat of Fusion of Ice
Purpose: Determine the heat of fusion of ice
Procedure:
1) Start with 100ml H2O at 50° C
2) Place into calorimeter (styrofoam cup) -record temp
3) Draw two or three ice cubes in and stir, don't run out of ice
4) Once temp stabilizes around 0°C remove ice (unmelted)
5) Measure new volume
Data:
Calculations:
1) Mass of 100kk H2O =100g
2) Cal q= m*^t*c = Q= 100g * 50° C * 4.18 kj/mol
3) Determine q ice = 16.720 kj/mol
4) Mass of ice melted = 80g H2O
5) Mole of melted ice = 4.4 mol H2O
6) ^ H of fusion for ice = 16,720/ 1000= 16.72 kj/mol
16.72/4.4 mol = 3.8 kj/mol
Conclusion:
Our heat of fusion was 3.8kj/mol. The final result had 36.7% error. We let the ice sit in the water for a while before we took the temperature which made a difference on the result.
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