Significant Figures


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Rachael_1H
Posts: 31
Joined: Fri Sep 25, 2015 3:00 am

Significant Figures

Postby Rachael_1H » Thu Feb 04, 2016 11:14 am

When Calculating K with the equation log K=(n)(standard E)/(0.0592), using the values log K=(2)(-.45 V)/(0.0592), K=6.27*10^-16 but the book rounds this value to K=6*10^-16.
Why is only one significant figure the correct amount of sig figs? Shouldn't it be 2 sig figs because the mantissa of the logarithm is to 2 decimal places?

GabrielaG 1J
Posts: 20
Joined: Fri Sep 25, 2015 3:00 am

Re: Significant Figures

Postby GabrielaG 1J » Thu Feb 04, 2016 4:34 pm

Yes, the answer should be K=6.27*10^-16 if the mantissa of the logarithm is to 2 decimal places. I wouldn't be too worried with the amount of significant figures the book shows since, in my experience, it hasn't always been accurate when it comes to sig figs.


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