9. Solutions

Which of the following compounds will have the highest boiling point?

Which of the following compound will have the highest vapor pressure?

The diagram to the right shows plots of vapor pressure versus temperature for a solvent and a solution.

b. What is the approximate boiling-point elevation for the solution?

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When 1 mol of HCl is added to 1 kg of water, the boiling point increases by 1.0 °C, but when 1 mol of acetic acid, CH₃CO₂H is added to 1 kg of water, the boiling point increases by only 0.5 °C. Explain.

HF is a weak electrolyte and HBr is a strong electrolyte. Which of the curves in the figure represents the change in the boiling point of an aqueous solution when 1 mole of HF is added to 1 kg of water, and which represents the change when 1 mol of HBr is added?

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Which of the following solutions will give rise to a greater osmotic pressure at equilibrium: 5.00 g of NaCl in 350.0 mL water or 35.0 g of glucose in 400.0 mL water? For NaCl, MW = 58.5 amu; for glucose, MW = 180 amu.

To prevent accumulation of ice on roads and sidewalks, many municipalities (and home-owners) will apply de-icing compounds to 'melt' the ice by lowering the freezing point.

b. Some de-icing compositions include dyes or colored compounds called indicators. Why?