How many moles of pbr3 contain 3.68 ã 1025 bromine atoms?

How many moles of pbr3 contain 3.68 ã 1025 bromine atoms?

Given data: # atoms of Br in PBr3 = 3.68 * 10^25 Explanation: In PBr3, 1 mole of PBr3 contains 3 moles of Br Now, 1 mole of Br contains Avogadro number i.e. 6.023 * 10^23 atoms of Br Therefore, the # moles of Br corresponding to 3.68*10^25 atoms would be: = 3.68 * 10^25 atoms * 1 mole Br/6.023*10^23 atoms = 61.099 moles of Br Since, 3 moles of Br is present in 1 mole of PBr3 then, 61.099 moles of Br would correspond to: 61.099 moles Br * 1 mole PBr3/3 moles Br = 20.366 moles of PBr3 Ans: 20.4 moles of PBr3

calculation by  use of Avogadro  law constant that is,   1  moles =  6.02  x10^23   atoms what   about  3.65  x10^25  atoms by   cross  multiplication = (1 mole  x 3.65 x  10 ^25  atoms)  /  ( 6.02  x10^23  atoms)  = 60.631  molesatoms and  atoms  cancel  out  each  other