Hello!
We have the following data:
m (mass) = ?
n (number of moles) = 5.20 moles
MM (Molar mass of C6H12)
C = 6*12 = 72 amu
H = 12*1 = 12 amu
--------------------------
MM (Molar mass of C6H12) = 72 + 12 = 84 g/mol
Now, let's find the mass, knowing that:
[tex]n = \dfrac{m}{MM} [/tex]
[tex]5.20\:\:\diagup\!\!\!\!\!\!\!mol = \dfrac{m}{84\:g/\diagup\!\!\!\!\!\!\!mol} [/tex]
[tex]m = 5.20*84[/tex]
[tex]\boxed{\boxed{m = 436.8\:g}}\end{array}}\qquad\checkmark[/tex]