I need help calculating Heat of fusion for a calorimeter experiment:
I know that Q(melt): 8350.46 J, m(ice): 26.39g and m(hot water): 51.93g. Please help me set it up. Hf known is 6.02kj/mol. Answer is in J/g(ice).
UPDATE: I got 352.49J/g. I need help figuring Hf in (kj/mol).
If you need further assistance you need to provide a few more details about exactly what you've done. To convert your answer of 352.49 J/g to kJ/mol, multiply that figures by the molar mass of H2O which gets you to J/mol and divide by 1000 to convert to kJ/mol. Your numbers are a little high. I think 334 J/g and 6.02 kJ/mol are the numbers found in the literature.
Hi: Thank you for helping me. I realized this after posting. I found that Hf is 5.7kj/mol and I know that the Hf known is 6.02kj/mol.
316.43*.001*18.02=5.70kj/mol
I found that 5.70/6.02= 94.7% <--Can you check if I did this correctly?
You have calculated the accuracy and not the % error. %error is 100-94.7 = 5.3%
Or to do it another way, this is what you do.
[(6.02-5.70)/6.02]*100 = same number above.
To calculate the heat of fusion (Hf) for the calorimeter experiment, you can apply the following formula:
Hf = Q(melt) / m(ice)
where:
- Hf is the heat of fusion (in J/g of ice).
- Q(melt) is the energy absorbed or released during the phase change (in J), which is given as 8350.46 J.
- m(ice) is the mass of the ice (in grams), which is given as 26.39 g.
Now, let's plug in the values into the formula:
Hf = 8350.46 J / 26.39 g
To convert the answer to J/g(ice), we need to convert the heat of fusion from J to kJ. Since the given Hf is 6.02 kJ/mol, we can use the molar mass of water to convert it to J/g(ice).
The molar mass of water (H2O) is approximately 18.015 g/mol. So, using this conversion factor:
Hf (J/g(ice)) = Hf (kJ/mol) * (1000 J/kJ) / (18.015 g/mol)
Now, let's plug in the value of Hf (J/g(ice)) and solve the equation:
Hf (J/g(ice)) = (6.02 kJ/mol) * (1000 J/kJ) / 18.015 g/mol
Therefore, to calculate the heat of fusion in J/g(ice) for the calorimeter experiment, you need to divide the energy absorbed during the phase change (Q(melt)) by the mass of the ice (m(ice)) and then convert it from kJ/mol to J/g(ice) using the molar mass of water.