Final answer:
Option C: To find the molarity of a KBr solution from its molality, one needs to consider both the density of the solution and the density of water, 0.0517 M.
Step-by-step explanation:
To calculate the molarity of a KBr solution, we need to convert the given molality to molarity. Given the molality (0.0710 m) and both the density of the solution (1.1 g/mL) and the density of water (0.997 g/mL), we can use the relationship between molality and molarity for dilute solutions and density information to find the molarity.
First, calculate the volume of the solution that contains 1 kg of water by dividing 1000 g (1 kg) by the density of water (0.997 g/mL), which gives us the volume of water in mL. Since the solution's density is 1.1 g/mL, to find the volume that such a solution of 1 kg water would occupy, we again divide 1000 g by 1.1 g/mL to get the volume in mL. Then, convert this volume to liters (L). Using the molality, we calculate the number of moles of KBr in 1 kg of water, which is also the volume we have just calculated. Finally, molarity is obtained by dividing the moles of solute by the volume of the solution in liters. This conversion accounts for the different units of molality (moles per kilogram of solvent) and molarity (moles per liter of solution).