Answer: Freezing point of a solution will be 
Explanation:
Depression in freezing point is given by:

= Depression in freezing point
i= vant hoff factor = 1 (for non electrolyte)
= freezing point constant = 
m= molality

Weight of solvent (benzene)= 1480 g =1.48 kg
Molar mass of solute (octane) = 114.0 g/mol
Mass of solute (octane) = 220 g



Thus the freezing point of a solution will be 
Answer:
b
Explanation:
[H3O+] = 10-pH = 10-3.4 ≅ 3.981 x 10^-4 moles/liter
Try this solution, all the details are described in the attached picture.
D. It has almost no hydrogen ions, therefore it is very basic.