how many decimal places to use for this chemistry lab?

Question

we have to fill a graduated cylinder with a certain amount of water (measured in millimeters), then we have to find the mass of that water in grams, then we have to find the density. in this class, we have to round to one more decimal place than the most precise measurement. however, the only measurement given to us on the lab sheet was the one reading "0 ml," which has no decimal places. i asked my teacher, and he basically said that we have to figure it out for ourselves. it's like a trick question. so, does anyone have an idea how many decimal places we should be rounding our measurements to. any information would be helpful! thank you! =]

Answer 1

Well first off, what was your most precise measurement?

From what you have written, I would say use your measured mL and add a second number to the end depending on where the water level was.



ex. If I were to see that it was 25.3 mL but a bit higher then you would put 25.35 mL and from there continue to use significant figures.



Good Luck





edit: well then use YOUR most precise data that you found... which would be the mL of water. From there use the same number of significant figures for the rest of the data.

Answer 2

The same number of Significant Figures as the least of a measurement on your sheet.

Answer 3

Let's say if the most precise measurement you obtained was 0.569, since your teacher said to round it to one more decimal place, then I would write it as 0.57



more examples:

0.548 --> 0.55

1.650 --> 1.70

2.399 --> 2.40



Then again, your teacher SHOULD tell you to how many decimals to round to.

I don't understand why he wont? Unless he's talking about the uncertainty and the significant figures?