How many atoms are in 0.40 mol of sulfur?

1 Answer
Feb 15, 2016

Answer:

In #1# #mol# of stuff, there are #6.022xx10^23# individual items of that stuff.

Explanation:

Now sulfur is non-molecular. Given the context of the question, I think I would be perfectly justified in giving the answer as:

#N_A# #"sulfur atoms"# #xx# #0.40*mol# #=# #6.022xx10^23*cancel(mol^-1)xx0.40*cancel(mol)# #=# #2.4xx10^23# individual sulfur atoms.

Had the question asked,

#"how many atoms are in 0.40 mol oxygen?"#,

I would have had to answer #4.8xx10^23# individual oxygen atoms, because it would contain the unstated assumption that oxygen is a binuclear gas, #O_2# (note that all the elemental gases, save the Noble Gases, are binuclear). Do you see the distinction I am trying to make?