How many atoms of Ba would be equal to 11.3 g of Ba?

4.96 x 10²²atoms

Explanation:

Given parameters

Mass of Ba  = 11.3g

Unknown:

Number of atoms  = ?

Solution:

To solve this problem, we need to find the number of moles of Ba first and then the number of atoms it contains.

    Number of moles  =  

  Molar mass of Ba = 137.3g/mol

  Number of moles  =   = 0.08mole

 1 mole of a substance contains 6.02 x 10²³ atoms

  0.08 mole of Ba will contain 0.08 x 6.02 x 10²³ atoms  = 4.96 x 10²²atoms

14 days is the half-life of phosphorus-32

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.