Assume ideal solutions at the same temperature a Which solution has the higher

# Assume ideal solutions at the same temperature a

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. Assume ideal solutions at the same temperature. a) Which solution has the higher osmotic pressure? urea Na 2 SO 4 they are equal ( Circle one): b) In order to stop water from flowing, pressure must be applied to which side of the tube? urea Na 2 SO 4 neither ( Circle one): c) If water is allowed to flow through the semipermeable membrane at a constant temperature, what will the concentration of Na 2 SO 4(aq) be when equilibrium is reached? (It might be helpful to break down concentration into moles solute per L solution and to consider that there is a total of 2 L of solution in the tube.) [Na 2 SO 4 ] = M 3 3 9 CHEM230 _W16 _PREP 3 _blank p 14 191) The standard boiling point of ethanol (C 2 H 6 O) is 78.4 o C. 9.15 g of a molecular solute dissolves in 100 g of ethanol. The vapor pressure of the resulting solution is 730.6 torr at 78.4 o C. a) What is the mole fraction of ethanol in the solution? (1 bar = 750.06 torr) X ethanol = b) What is the molar mass of the solute? MW solute = g/mol c) What is the boiling point of the solution? (k b (ethanol) = 1.07 ( o C kg)/mol) T boiling = o C 6 8 6 CHEM230 _W16 _PREP 3 _blank p 15 b) Rank the following saturated aqueous solutions (all at the same temperature) in order of increasing osmotic pressure: Ag(IO 3 ) (K sp = 3.17x10 -8 ), Ba(IO 3 ) 2 (K sp = 4.01x10 -4 ), and Cr(IO 3 ) 3 (K sp = 5x10 -6 ). Write the name of one salt in each box. lowest osmotic pressure < < highest osmotic pressure 198) Find the osmotic pressure of a saturated solution of Cr(IO 3 ) 3 (K sp = 5x10 -6 ) at 298K. Π = atm c) What is the Δ H hyd of IO 3 - given the follwing data: Δ H hyd (Na + ) = -406 kJ/mol; Δ H lat (NaIO 3 ) = 766 kJ/mol; Δ H sol (NaIO 3 ) = 20.3 kJ/mol d) What mass of NaIO 3(s) (MW =197.89) must be added to 250 mL of a 0.086 M solution of Cr +3 (aq) in order for start precipitate formation. (You may need data provided earlier in the problem.) mass NaIO 3 g 12 8 Δ H hyd (IO 3 - ) = kJ/mol 4 8 CHEM230 _W16 _PREP 3 _blank p 16 199) a) Data shows that carbon dioxide (CO 2 ) has a solubility of 0.3346 g CO 2 per 100 mL of water at 273K when the partial pressure of CO 2 is 1 atm. a) Find the Henry's law (k H ) constant for CO 2 in water at 273K in molality units: mol/(kg bar). Use units of bar for pressure. Assume the density of water is 1.0 g/mL. mol kg bar k H = b) In J. Chem. Educ. ( 87, 2010, 993) it is reported that the freezing point for an unopened can of LaCroix brand sparkling water is -0.49 o C. Given the k f for water is 1.86 ( o C kg)/mol, what is the partial pressure of CO 2 in the can? P CO2 = bar 6 8 200) Two beakers, one containing 0.01 m NaNO 3(aq) and the other containing 0.01 m Fe(NO 3 ) 3(aq) are placed inside a bell jar and sealed. The beakers are left until the water vapor has come to equilibrium with any liquid in the container. The levels of the liquid in each beaker at the beginning of the experiment are both at the 1L mark as pictured. Draw the relative levels of the liquid at equilibrium. If there is no change in the liquid level, write no change. 1L NaNO 3(aq) 1L Fe(NO 3 ) 3(aq) 4 CHEM230 _W16 _PREP 3 _blank p 17 Inspite of the fact that silver nitrate (AgNO 3 MW = 169.87) is considered a soluble salt, it does have a limited solubility in water. The maximum solubility of AgNO 3 is 206g in 100 mL of water at 25 o C.  • • • 