Show all work for all calculations Initial water temperature, : 8 C Final water
ID: 1046074 • Letter: S
Question
Show all work for all calculations Initial water temperature, : 8 C Final water temperature, 1 Change in water temperature, ?: Initial water volume, V Final water volume, V Volume of melt, AV Mass of water cooled Mass of ice melted: Heat released by cooling water oC 50 mL mL Calculated Heat of fusion:J/g Molar heat of fusion: J/mol H fusion Percent error: Conclusions: a) In what way does calorimetry make use of the Law of Conservation of Energy? b) Is the process of melting exothermic or endothermic? Give evidence from this lab to support your answer.Explanation / Answer
To calculate heat released by cooling water-
Q=m.c.?T
Q=50 gm.4.18.44.5°C
Q=9300.5J
To calculate Heat of fusion
Q=m.?H
?H=Q/m=9300.5/50=186.01 j/g
Therefore?H = 186.01 j/gm
To calculate molar heat of fusion
?Hf= 186.01 * 18.0 = 3356.1 j/mol
Molar heat %error
Accepted value for molar heat is 6.01 kj/mol
%error= 3356.1 - 6010/6010*100
%error = 44.15%
Conclusion:
a) law of conservation states that"energy is neither created nor destroyed but remains constant in given system"
In experiment heat lost = heat gained
Hence energy is not lost it is conserved.
From this calorimeter make use of it.
b) Melting is an endothermic process
Evidence for this is-
Take warm water in a beaker put a thermometer in it.and check temperature.then add some ice cubes and observe temperature going down.
Process of melting needs some energy which it gained from warm water.