A solution is prepared by dissolving 5.85 g of sodium chloride (NaCl) in 100 g of water. Calculate the molality of the solution.

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We need to calculate the molality of a solution made by dissolving five point eight five grams of sodium chloride in one hundred grams of water. Molality is defined as moles of solute per kilogram of solvent. Let's work through this step by step. First, we need to calculate the molar mass of sodium chloride. The molar mass of sodium is twenty two point nine nine grams per mole, and the molar mass of chlorine is thirty five point four five grams per mole. Adding these together gives us fifty eight point four four grams per mole for sodium chloride. Now we calculate the number of moles of sodium chloride using the formula: moles equals mass divided by molar mass. We have five point eight five grams divided by fifty eight point four four grams per mole, which gives us zero point one zero zero one moles of sodium chloride. Next, we convert the mass of water from grams to kilograms. One hundred grams equals zero point one zero zero kilograms. Finally, we calculate molality by dividing moles of solute by kilograms of solvent: zero point one zero zero one moles divided by zero point one zero zero kilograms equals one point zero zero one molal, which rounds to one point zero zero molal. To summarize our calculation: We found the molar mass of sodium chloride to be fifty eight point four four grams per mole. We calculated zero point one zero zero one moles of sodium chloride from five point eight five grams. We converted one hundred grams of water to zero point one zero zero kilograms. Using the molality formula, we determined the final answer to be one point zero zero molal.