A college student is trying to determine thefreezing point of an aqueous solution. Heknow it will be less than 0°C because of theconcept of freezing point depression (waterhas a freezing point of 0°C, so the solution willhave one lower). Here is the information hehas:· Solute: Ammonium phosphate,(NH4)3PO4, molar mass of approximately149 g/mol. i = 4Kf for water = -1.86 °C/m· Amount of solute: 74.5 g (NH4)3PO4· Amount of water (solvent): 425 g H201) Calculate the molality (m = mol solute / kg%3Dsolvent).2) Determine the freezing point of thesolution; show your work.3) Suppose he switched the ammoniumphosphate for a different solute, potassiumchloride. Explain how that change would alterthe freezing point. Justify your answermathematically.

As a non volatile substance is added to a solvent,the freezing point of solvent is depressed. It is…

A college student is trying to determine the freezing point of an aqueous solution. He know it will be less than 0°C because of the concept of freezing point depression (water has a freezing point of 0°C, so the solution will have one lower). Here is the information he has: · Solute: Ammonium phosphate, (NH4)3PO4 , molar mass of approximately 149 g/mol . i = 4 • KĘ for water = -; -1.86 °C/m · Amount of solute: 74.5 g (NH4)3PO4 · Amount of water (solvent): 425 g H20 1) Calculate the molality (m = mol solute / kg solvent). 2) Determine the freezing point of the solution; show your work. 3) Suppose he switched the ammonium phosphate for a different solute, potassium chloride. Explain how that change would alter the freezing point. Justify your answer mathematically.

A college student is trying to determine the freezing point of an aqueous solution. He know it will be less than 0°C because of the concept of freezing point depression (water has a freezing point of 0°C, so the solution will have one lower). Here is the information he has: · Solute: Ammonium phosphate, (NH4)3PO4 , molar mass of approximately 149 g/mol . i = 4 • KĘ for water = -; -1.86 °C/m · Amount of solute: 74.5 g (NH4)3PO4 · Amount of water (solvent): 425 g H20 1) Calculate the molality (m = mol solute / kg solvent). 2) Determine the freezing point of the solution; show your work. 3) Suppose he switched the ammonium phosphate for a different solute, potassium chloride. Explain how that change would alter the freezing point. Justify your answer mathematically.

Chemistry: Principles and Practice

3rd Edition

ISBN:9780534420123

Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Publisher:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Chapter12: Solutions

Section: Chapter Questions

Problem 12.95QE

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