Question

The radius of a krypton atom is 110pm and it's mass is 1.39x10 to -22 g.

Answer 1

Answer:

$24.9~g/cm^3$

Explanation:

Density is found dividing mass by volume. In this case, we treat krypton as a sphere having a volume of $V = \dfrac{4}{3}\pi r^3$. Given:

$m = 1.39\cdot 10^{-22}~g$

$r = 110 pm = 1.10\cdot 10^{-8}~cm$

We obtain density of:

$d = \dfrac{m}{V} = \dfrac{m}{\dfrac{4}{3}\pi r^3} = \dfrac{3m}{4\pi r^3}$

$d = \dfrac{3\cdot 1.39\cdot 10^{-22}~g}{4\pi\cdot (1.10\cdot 10^{-8}~cm)^3} = 24.9~g/cm^3$

This is not a feasible value for a gas like krypton, its radius is actually not 110 pm.