In #"2 L"# of a #"2.00 M"# solution of #"AgNO"_3#, which of the following is/are true?
#a)# The concentration is #"4.00 M"# .
#b)# In #"1 L"# of the solution, there are #"4.00 mols"# of #"AgNO"_3# .
#c)# The mass of #"AgNO"_3# dissolved in #"1 L"# is greater than #"300 g"# .
#d)# In a #"500.00 mL"# aliquot, you have less mols of #"AgNO"_3# .
1 Answer
Well, using the properties that concentration is intensive and mols are extensive, the mols must be smaller, and the concentration must be the same.
This cannot be true, because it directly contradicts the question.
In
#"1 L"# of solution, there are#"2.00 mols"# , as stated in the concentration, not#"4.00 mols"# .Originally you had
#"4.00 mols"# in the#"2 L"# , but you only took half of it, so you only took half the total#"mols"# .
#2.00 cancel("mols AgNO"_3) xx ("107.9 g Ag" + "14.007 g N" + 3 xx "15.999 g O")/cancel("1 mol AgNO"_3)#
#=# #"339.8 g"# in
#"1 L"# . So this is true... if "dissolved solute" refers to#"AgNO"_3(s)# dissolved. The solubility is around#"2560 g"/"1 L"# at#25^@ "C"# , so this is easily doable.
This is also true. Concentration does not depend on the volume you pick out, because you also pick out the proportional amount of moles.
