a) The element with the greatest density is osmium, which has a density of 22.6g/cm3. calculate the mass of 32.1 cm3 of osmium.

Answer: 22.6g x 32.1 = 725.46
Did I have right answer?

b) A team of students determined the density of a sample of wood to be 0.52g/cm3. A handbook of chemistry reported the density of 0.548g/cm3 for the same type of wood. what is the percent error of the students value?
anser:(0.548 - 0.52) / 0.548 x 100 = 5.1%
Can someone check my answer for me?

2 answers

B is ok.
A is exactly correct; however, you have too many significant figures in the answer. You are allowed only 3 (both 32.1 and 22.6 have three); therefore, you are allowed just 3. Thus, I would round the answer to 725 AND I would put a unit on it of "grams."
a) mass 32.1 / density 22.6 = volume answer: 1.42g volume