general chemistry
posted by melissa .
the radius of a chlorine atom is 99 pm and its mass is 5.89 X 10^23 grams what is the density

I am assuming that 99pm means pico meters, so 99pm = 99 x 10^7 cm
D=mass(g)/volume(cm3)
Plug in the value for radius into the equation to solve for the volume which will have units of cm^3
v=4/3πr^3
Since density=mass(g)/volume(cm3),
Solve for density,
D= (5.89 X 10^23 g/volume calculated in cm^3) 
so to get volume, you do v=(1.33)*3.14*99e7^3????

Yes.

But, I gave you the wrong units for 99pm in cm, it should be 99x10^10. I apologize about that