12. Mercury (Hg) has a density of 13.5336 g/cm³. How many mL of mercury are required to have the same number of mercury atoms as the number of water molecules in a 250.0 mL sample of water (d = 1 g/cm³ exact)?

A. 18.47mL Hg

B. 205.7mL Hg

C. 8.357 x 10²⁴ mL H₂O

D. 31.15 mL H₂O

E. None of the above.

13. How many molecules of benzene (C₆H₆, d = 0.8765g/cm³) are present in a 2.005mL sample of benzene (Avogadros number is 6.022x10²³)?

A. 1.545 x 10²² molecules of benzene

B. 1.355 x 10²² molecules of benzene

C. 2.248 x 10^-2 molecules of benzene

D. 1.058 x 10²⁴ molecules of benzene

E. None of the above.