A piece of platinum metal with a density of 21.5 g/cm^3 has a volume of 4.49 cm^3. What is its mass?

1 Answer
Jun 6, 2017

Answer:

#96.5g#

Explanation:

Use the formula for density but rearrange the formula to solve for mass:

#d=m/v# where #d# is the density in #g/(cm^3)#, #m# is the mass in #g#, and #v# is the volume in #cm^3#:

Given the information we can write a formula like so:

#21.5=m/4.49#

We are trying to find the mass so we can rewrite the equation such that we solve for #m#:

#4.49*21.5=m/cancel(4.49)cancel(4.49)#

#4.49*21.5=m#

#96.533=m#

#96.5g=m# (With proper sigfigs)

We could check this answer by substituting our newly found mass and given volume to find density. In doing this, we should get #21.5g/(cm^3)# because that's what the problem told us;

Check:
#d=96.5/4.49#

#d=21.5#