How many atoms of oxygen are contained in 47.6 g of #Al_2(CO_3)_3#? The molar mass of #Al_2(CO_3)_3# is 233.99 g/mol.

1 Answer
Sep 20, 2016

There are #9xx0.203*molxx6.022xx10^23*mol^-1# oxygen atoms in a #47.6*g# mass of #Al_2(CO_3)_3#.

Explanation:

In the one mole of #Al_2(CO_3)_3# there are #N_A# formula units, i.e. #6.022xx10^23# formula units.

#"Moles of aluminum carbonate"# #=# #"Mass"/"Molar mass"#

#=# #(47.6*g)/(233.99*g*mol^-1)# #=# #0.203*mol#

But in each mole of the carbonate there are clearly #9# #mol# #O# atoms.

And thus there are #9xx0.203*mol# #O# atoms in the given quantity.