Chem question Kaplan Pg531

[Glowwyrm]

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I have the 2007 edition but I think the 2006-2007 edition is the same.

Page 531 #4 asks:
Calculate the amount of heat needed to bring 10 g of ice from -15C to 100C.

In their solution it looks as though they are converting C to K. I'm not sure why they are getting 15K, 100K, and 10K. Anyone with this book know if it's a typo and they actually mean C instead of K? Still, we'd need to convert to K so that we would end up with the correct units for the answer. Does the 2006-2007 edition also have this as the solution?

 

[tivon]

I have the 2007 edition but I think the 2006-2007 edition is the same.

Page 531 #4 asks:
Calculate the amount of heat needed to bring 10 g of ice from -15C to 100C.

In their solution it looks as though they are converting C to K. I'm not sure why they are getting 15K, 100K, and 10K. Anyone with this book know if it's a typo and they actually mean C instead of K? Still, we'd need to convert to K so that we would end up with the correct units for the answer. Does the 2006-2007 edition also have this as the solution?

The book is correct.
The given heat capcities have cal/ g K units, so we must convert delta T to K. Delta T in K degree has the same value with delta T in C degree. For example, we need to calculate delta T from 0 C to 100 C.
Delta T (K)=(100+273)-(0+273)=100 K
Delta T (C)=100-0 =100 C
I hope that it helps.

 

[Glowwyrm]

Ah that makes perfect sense. Yes it does help. Thanks so much.