If the theoretical density of UO2 is 1097 gcm3 determine the

If the theoretical density of UO₂ is 10.97 g/cm³, determine the atomic density of U-235 in a typical sintered fuel pellet enriched to 3.5 w/o. Anwer is 8.24 x 10²⁰/cm³

Solution

U-235 enrichment by weight = 3.5%

molecular weight of UO₂   = 238+2*16 = 270

1 mole of any substance contains 6.02e+23 molecules/atoms

1 cc of UO₂ contains 10.97 gms

                                      = 10.97/270 moles

for each molecule of contains 1 U atom or 0.035 atoms of U-235 and 0.965 atoms of U-238

aromic density of U-235 in the given sample = (10.97/270)*6.02e+23 *0.035

                                                                        = 8.56e+20 atoms /cc