Question

Osmium (os) is the densest element known (density = 22.57 g/cm3). Calculate the mass in pounds and in kilograms of an os sphere 15 cm in diameter, about the size of a grapefruit. Enter your answers in scientific notation.

Answer 1

Answer:

    Mass in kg = 39.88

    Mass in pounds = 87.92

Explanation:

   We have the expression for Density, ρ = Mass / Volume, in this case density is given and we need to find mass and volume.

   Volume of a sphere, we have the expression $V = \frac{4}{3} \pi r^3$, where r is the radius of sphere.

   Radius of sphere, r = Half of diameter = 15/2 = 7.5 cm

   So $V = \frac{4}{3}* \pi* 7.5^3 = 1767.15 cm^3$

  Mass = Volume *  Density = 1767.15*22.57 = 39884.49 g

    Mass in kg = 39884.49/1000 = 39.88 kg

    Mass in pounds = 39.88*2.205 = 87.92 lb