How many atoms are found in a 15.5 g sample of bismuth?


Answer :

Answer:

4.47 x 10²² atoms

Explanation:

Given parameters:

Mass of Bismuth  = 15.5g

Unknown:

Number of atoms  = ?

Solution:

To find the number atoms, first solve for the number of moles in this element first.

  Number of moles  = [tex]\frac{mass}{molar mass}[/tex]    

  Number of moles  = [tex]\frac{15.5}{209}[/tex]    = 0.074mole

So:

        1 mole of a substance contains 6.02 x 10²³ atoms

     0.074 mole of Bismuth will contain 0.074 x 6.02 x 10²³ atoms

                                                          = 4.47 x 10²² atoms