Perform the calculation and report the answer using the proper number of significant figures.

Question

Perform the calculation and report the answer using the proper number of significant figures.

Make sure the answer is rounded correctly.

1.012×10−3 J/ (0.025456 g)(298.3682−298.3567) K

= 3.60 J/g⋅K

I got 3.60 and my homework application keeps saying its wrong, help :(

Answer 1

I got the following:

1.012x10^-3 J / (0.025456g)(0.0115K) = 3.46 J/g/degree K (to 3 significant figures)

The three sig. figs. is based on only 3 s.f. in temperature value 0.0115 K

Answer 2

Hi Angie G.,

You did the math wrong somehow. = 1/012*10^-3/0.025456/0.0115 = 3.46 as rounded (with units, of course). Probably a keystroke error?

You were correct to detect that the temperature differences yield only 3 sig figs.

Small consolation to you: sig figs are only used in middle school and high school science. Beyond that, indeterminate error is chased using variances, and stated as 95% probability limits on reported results. So that you don't detect 3 sig figs for 999 sheep, but 4 sig figs for 1000 sheep ....

-- Cheers, -- Mr. d.