Identify the correct statements : A. The molality of 2.5 g of ethanoic acid (Molar mass : 60 g mol ⁻¹ ) in 75 g of benzene solution is 0.556 m. B. The molarity of a solution containing 5 g of NaOH (molar mass : 40 g mol ⁻¹ ) in 450 mL of solution is 0.278 M at 298 K. C. Aquatic species are more comfortable in cold water. D. The solubility of gas increases with decrease in pressure. E. For a binary mixture of A and B,

Step-by-step solution

Statement A : Molality is given by the number of moles of solute divided by the mass of solvent in kg. Moles of ethanoic acid = 2.5 60 = 1 24 mol Mass of benzene = 75 g = 0.075 kg Molality = 1/24 0.075 = 1000 24 75 = 1000 1800 = 5 9 = 0.556 m Statement A is correct. Statement B : Molarity is given by the number of moles of solute divided by the volume of solution in litres. Moles of NaOH = 5 40 = 1 8 mol Volume of solution = 450 mL = 0.45 L Molarity = 1/8 0.45 = 1000 8 450 = 1000 3600 = 5 18 = 0.278 M Statement B i