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Significant Figure Problem

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CJP4:
Ok... i dunno why it's saying it's wrong but here's my problem.

Given:
A certain reaction has H° = +17.3 kJ and S° = +39.7 J/K.

Question:
c) Calculate G° for the reaction at 298 K.
 Check the number of significant figures. kJ

deltaG=(deltaH)-(Temp)(deltaS)

I did (17.3kJ)-(298K)(.0397)=5.4694

So the answer should be 5.47 in sig fig, but it says it's wrong and i have 1 more try and don't wanna lose the point lol.  Anyone think it should be 5.46? if so why?

add: it should be correct just the sig fig wrong because "Check the number of significant figures. kJ" only comes up when the sig fig is wrong supposedly.

mike:
What do you mean by "it says its wrong"? is it an answer in a book? computer?

does it tell you the right answer?

CJP4:
Hrm i think my homework site is just stupid.

I just did a problem that obviously again only had 3 sig fig.

Data: H° = -844 kJ ; S° = -94.8 J/K ; 298K

But the answer came out as -815.7kJ.. 4 sig fig....

Err well all the problems in this that have red text are different for each student and i guess when they randomize it they don't do the sig fig correctly... i will consult my teacher i guess  >:(

CJP4:

--- Quote from: mike on October 04, 2005, 10:15:09 PM ---What do you mean by "it says its wrong"? is it an answer in a book? computer?

does it tell you the right answer?

--- End quote ---

it's a homework site.  You get 5 chances for each answer.

It puts a green check by the answer if correct.

It puts a red X by the answer if incorrect.

If it's correct, but says the significant figures is wrong it puts a red X and says " check your significant figures "

Ya Ya i know... it's kinda making me mad.  That answer should be right  :'(

mike:
Yeah that kinda sux when they do that!

Maybe inform the teacher or instructor..

good luck :)

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