How many atoms are in a mole of barium chloride, #BaCl_2#?

1 Answer
Feb 11, 2016

Clearly there are #3# #"moles"# of atoms in one mole of #BaCl_2#.

Explanation:

If I asked how many atoms there were in a dozen formula units of #BaCl_2#, I think you would quickly answer 3 dozen: 12 barium atoms, and 24 chlorine atoms.

The question specified molar quantities, and the mole is just another number, admittedly a very large number, i.e. #N_A# #=# #6.022xx10^23# #mol^-1#.

So in #1# mole of #BaCl_2#, there are #3# #xx# #N_A# barium and chlorine atoms, where #N_A# is Avogadro's number, #6.022xx10^23#.

What is the actual mass of this quantity of barium chloride?