The density of concentrated sulfuric acid is 1.84 g/mL. If this corresponds to 18 M, what is the molality of the solution?

Question

Molar mass= 98.
98 x 18 =1764g/L - 1.84 =1762.16/1000 = 1.76 kg
18/1.76=10.23 m

But my only options are:
a) 18 m
b) 95.5 m
c) 240 m
d) 0.240 m?

Answer 1

18 mols x 98 g/mol = 1764 grams/L of H2SO4.
mass solution is 1.84 x 1000 = 1840 grams.
mass H2O then is 1840-1764 = 76 grams.
m = mol/kg solvent = 18/0.076 = ?