15. Calculate the concentration (molarity) of a glucose solution containing 0.1 moles of glucose in 0.4 liters of water.
A. 0.25 mol.L-1
B. 4.0 mol.L-1
C. 2.5 mol.L-1
D. 2 mol.L-1
.1mol/.4L=.25 mol. L-1. So I got this for the answer but I was confused why the answer is exact and not 1 sig fig (.2)
Module: Molarity #15
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Re: Module: Molarity #15
I don't think multiple choice questions are as stringent on significant figures.
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Re: Module: Molarity #15
That is strange! I would say to always keep the habit of putting the correct sig figs regardless because it's 1 point off per question on the midterms and finals!
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Re: Module: Molarity #15
I'm not sure either, but I refer back to the given information of the problem when determining the number of significant figures in my answer. You shouldn't have more significant figures in your answer than was present in the information with the least number of significant figures in the question. At least you got the answer right!
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Re: Module: Molarity #15
On the actual test you would round 0.25 to 0.2 because of sig figs, but I think that the answer is 0.25 on this question is to prevent confusion since people may not be considering sig figs while taking the assessment.
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Re: Module: Molarity #15
Since 0.25 isn't followed by any other decimal values after the 5, normally this answer would and should be rounded to 0.2 since both of the values getting you to this answer had only one significant figure.
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