At 75 the vapor pressure of water methanol diethylether and benzene are 289

At 75 the vapor pressure of water methanol

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At 75, the vapor pressure of water, methanol,diethylether and benzene are 289, 1126, 2680,and 644 torr, respectively. Which of these isNOT above its boiling point at normal atmo-spheric pressure? 1.methanol and diethylether2.None of these3.water and benzenecorrect4.methanol, diethylether, and benzene5.water Methanol and diethylether are well above 760 torr at this temperature which means they are above their normal boiling points. 013 10.0 points Each of the following samples was placed in 1 liter of water. I) 0.6 mol NaOH II) 0.7 mol KCl III) 0.5 mol Na 2 NO 3 IV) 1 mol of sugar Rank the solutions that are made in terms of increasing order of boiling point elevation. (Remember your solubility rules.) 1. IV, I, II, III correct 2. IV, II, I, III 3. III, I, IV, II 4. II, IV, I, III 5. III, I, II, IV Explanation: Colligative properties of a solution depend on the number of solute particles in solution, not the type. I) will have 1.2 mol of particles because NaOH completely dissociates in water. II) will have 1.4 mol of particles because KCl completely dissociates in water. III) will have 1.5 mol of particles because Na 2 CO 3 completely dissociates in water. IV) will have 1 mol of sugar in solution because it is soluble but does not dissociate. The higher the concentration, the greater the boiling point elevation, so 014 10.0 points Polyacrylamide is a water-soluble polymerwhose aqueous solution containing 25 g/L de-velops an osmotic pressure of 0.54 torr at25C. Find the approximate molecular weightof the polymer sample.
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– Homework #2 – Holcombe – (51055) 5
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  • Fall '07
  • Holcombe
  • Chemistry, Vapor pressure, Torr

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