Question

This is a practice quiz and I want to make sure I have the correct answers, please help! thank you!

In the text I said it was a practice quiz

1. Liquid aluminum will crystalize with a face-centered cubic (fce) unit cell. Face-centered cubic unit cells contain 8 atoms per unit cell. Determine the density of solid aluminum if the radius of an aluminum atom is measured to be 143 pm. (Hint: Calculate the mass and volume to determine the densityd m/V) Length- 2V 2r 2. Rank the following compounds in order of increasing attraction between their ions: KBr, SrBr, and CsBr. Explain your reasoning. 3. Rank the following ionic compounds in order of smallest to largest energy required to separate the ions. CaF KF NaF MgF2 LiC Explain your reasoning 4. Which of the solutions shown here will have the lowest vapor pressure? White circles indicate solvent molecules; black cireles indicate molecules of a nonvolatile solute. C. a. d. b. S. In the following Born-Haber cycle for the formation of sodium chloride from its elements, which step (A-E) corresponds to the lattice energy for NaCl? Na (g)+ Cig) Natig)+ Cg) D Na (g) Crg) + Na(g)+ Ciig) B Naig) +0.5 Clyla) E A Na(s)+0.5 Cly(g) NaCl(s) 6. What is the vapor pressure of an aqueous solution that has a solute mol fraction of x 0.100? The vapor pressure of water is 25.756 mm Hg at 25°C. 7.A solution contains 6.50 mol water, 0.300 mol sucrose, and 0.200 mol glucose. The solutes are nonvolatile. What is the vapor pressure of the solution at 35°C given that the vapor pressure of water is 42.2 torr? 8. Indicate which aqueous solution has the lowest vapor pressure. 0.1 MKCI b. 0.1 M Na CO d. 0.1 MMgCl e. 0.2 M MgCl a. 0.2 M NaCl c. 9. A solution is prepared by mixing 50 g of methanol (CH,OH) with 50 g of ethanol (CH2CH2OH). Use the following data to determine the vapor pressure of this solution at 20°C. Substance Vapor Pressure at 20°C (torr) 92 45 Methanol Ethanol 10. What is the boiling point of a 3.25 m KCI solution (Ks 0.52°C/m for water)? 11. Magnesium chloride is often used to melt ice on sidewalks. Considering that the solubility of magnesium chloride (95.21 g/mol) in water is 54.3 g per 100.0 g of water, what is the lowest temperature that you would expect to be able to melt ice with magnesium chloride? Assume ideal behavior. Kr(water) 1.86 C/m 12. Which of the following solutions, assuming equal volumes and a nonvolatile solute, would have the highest boiling point? Provide rationale for your choice. II II IV 1. Liquid aluminum will crystalize with a face-centered cubic (fee) unit cell. Face-centered cubic unit cells contain 8 atoms per unit cell. Determine the density of solid aluminum if the radius of an aluminum atom is measured to be 143 pm. (Hint: Calculate the mass and volume to determine the density-d m/V) Length- 2 2r 2. Rank the following compounds in order of increasing attraction between their ions: KBr, SrBr, and CsBr. Explain your reasoning. 3. Rank the following ionic compounds in order of smallest to largest energy required to separate the ions. CaF KF NaF MgF2 LiC Explain your reasoning 4. Which of the solutions shown here will have the lowest vapor pressure? White circles indicate solvent molecules; black cireles indicate molecules of a nonvolatile solute. C. a. d. b. S. In the following Born-Haber cycle for the formation of sodium chloride from its elements, which step (A-E) corresponds to the lattice energy for NaCl? Nag)+ Clg) Nat() +CIa) D Na (g) CHg) + Na(g)+ Cl(g) B Naig) +0.5 Clyla) E A Na(s)+0.5 Cl(g) NaCl(s) 6. What is the vapor pressure of an aqueous solution that has a solute mol fraction of x 0.100? The vapor pressure of water is 25.756 mm Hg at 25°C. 7.A solution contains 6.50 mol water, 0.300 mol sucrose, and 0.200 mol glucose. The solutes are nonvolatile. What is the vapor pressure of the solution at 35°C given that the vapor pressure of water is 42.2 torr? 8. Indicate which aqueous solution has the lowest vapor pressure. 0.1 MKCI b. 0.1 M Na CO d. 0.1 MMgCl e. 0.2 M MgCl a. 0.2 M NaCl c. 9. A solution is prepared by mixing 50 g of methanol (CH,OH) with 50 g of ethanol (CH3CH2OH). Use the following data to determine the vapor pressure of this solution at 20°C. Substance Vapor Pressure at 20°C (torr) 92 45 Methanol Ethanol 10. What is the boiling point of a 3.25 m KCI solution (Ks 0.52°C/m for water)? 11. Magnesium chloride is often used to melt ice on sidewalks. Considering that the solubility of magnesium chloride (95.21 g/mol) in water is 54.3 g per 100.0 g of water, what is the lowest temperature that you would expect to be able to melt ice with magnesium chloride? Assume ideal behavior. Kr(water) 1.86 C/m 12. Which of the following solutions, assuming equal volumes and a nonvolatile solute, would have the highest boiling point? Provide rationale for your choice. II II IV

Answer 1

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Gree Date Page No. Zx M NA -23 e &35. 841 6.5 X 10-3 cm S.SIY