If the density of silver is 10.5 g/mL, what is the mass of 3.7 mL of silver?

Question

I need to be shown how to work out this peoblem.

Answer 1

To find mass from the density, you should do as Victoria said, multiply the volume and the density.  The mL cancel out leaving you with grams, which is a measure of mass.  But be careful, in Chemistry class (and most scientific classes) you need to report your answer correctly to the right number of significant digits or figures (sig figs). 

 

In this case, your density has 3 sig figs, but the volume has only 2 sig figs. Therefore, your answer should be rounded to 2 sig figs.

 

For this problem the answer 38.85 grams would be rounded to 39 grams.

Answer 2

If the density has units of grams/mL.  And you want mass (grams), just need to multiply by grams/mL by mL and you get grams.

 

So 10.5 grams/mL * 3.7 mL = 38.85 grams.