Can someone just point me in the right direction w/ this, I need to know the volume of Pb-208, which has a mass of 3.45x10E-22 g and a diameter of 3.5x10e-10 m. I have a lot of questions to answer here but they all require the volume first, so what is the best way to approach this to find the volume in cm3? I'm really confused!
PS: I'm not really looking for the answer just the approach to get to the answer. Thanks
2007-07-22 05:29:48 · 2 answers · asked by camdfw 3 in Science & Mathematics ➔ Chemistry
We assume a spherical shape .
V = 4/3 x 3.14 x r^3
d = 3.5 x 10^-10 m
r = 1.75 x 10^-10 m = 1.75 x 10^-8 cm
V = 4/3 x 3.14 x ( 1.75 x 10^-8)^3 = 2.24 x 10^-23 cm^3
If you need density :
d = mass / V = 3.45 x 10^-22 / 2.24 x 10^-23 = 15.4 g/cm^3
To Maussy:
this result may not be false because Pb-208 is an isotope of Pb. The value of the density that you have found is the density of Pb in which are considered all isotopes.
2007-07-22 05:41:44 · answer #1 · answered by Dr.A 7 · 0⤊ 0⤋
if you assume as spherical shape volume is
V=4/3 *pi*r^3=4/3*pi*(1.7510^-10)^3=2.245*10^-29m^3
Its density is 3.45*10^-22/2.245*10^-29=1.54*10^7kg/m^3
this corresponds to a density of 15.3
However, this result is false since in the table, the density is 11.34
2007-07-22 13:38:53 · answer #2 · answered by maussy 7 · 0⤊ 0⤋