How many liters of #Br_2# are in a container at STP that contains 2.25 moles of #Br_2#?

1 Answer
Jan 25, 2016

Answer:

Approx. #100# #mL# . Why?

Explanation:

We need to know the density of elemental bromine. #rho# #=# #3.11# #g*mL^-1# at STP.

Now there are #2.25# #mol# of stuff; i.e. there are #2.25# #cancel(mol)# #xx# #2xx79.90# #g*cancel(mol^-1)# #=# #359.55# #g#. (Note that I mulitplied by 2 in order to account for the molecularity of elemental bromine; it is #79.9# #g*mol^-1# for the bromine ATOM!)

Using the density, #rho#, this is #(359.55*cancelg)/(3.11*cancelg*mL^-1)# #~=# #100# #mL# #=# #??L#

There are few things in the laboratory that are as corrosive as bromine; it can cause horrendous burns, and this quantity would be treated with respect.