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Topic: Thermochemistry answer check please??  (Read 4577 times)

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Offline soolee

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Thermochemistry answer check please??
« on: February 06, 2015, 12:23:57 AM »
Did I do this problem correctly??

If you supply 36 kJ of heat, how many moles of ice at 0 C can be melted, heated to its boiling point, and
completely boiled away? ( H = 40.5 kJ/mol; H = 6.0 kJ/mol; specific heatwater = 0.0753 )

Total heat = heat to melt ice + heat to warm water to 100 C + heat to evaporate water 
Total heat = (moles ice  H ) + (moles water  C T) + (moles water  H ) 
36 kJ = (moles of H O  6.0 kJ/mol) + (moles of H O  0.0753   100 C) + (moles of H O 
40.5 kJ/mol) 
36 kJ = moles H O (6.0 kJ/mol + 0.0753   100 C + 40.5 kJ/mol) 
36 kJ = moles H O (54.0 kJ/mol) 
moles H O =   
moles H O = 0.67 mols??


thank you for your help


Offline Borek

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Re: Thermochemistry answer check please??
« Reply #1 on: February 06, 2015, 02:42:04 AM »
Thanks to your use of H and O it is about as obscure as it can be. There is still room for improvement though, you could make it even harder posting in Swahili.

That being said, logic behind what I was able to guess looks correct.
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