CHEM 2 CH 13 LS

Which of the following statements correctly describe solubility?

-A concentrated solution contains a relatively large amount of solute in a given amount of solvent -The solubility of a given substance in a particular solvent varies with temperature

Which of the following statements correctly describe gas-liquid solutions?

-A nonpolar gas solution will not dissolve readily in a polar solvent -Gases appear to be more soluble in aqueous solutions if they react with H2O after dissolving -A polar gas will dissolve readily in a polar solvent

Which of the following compounds are expected to be soluble in carbon tetrachloride?

-CO2 -C6H6

Which of the following statements correctly describe solutions comprising of gases and/or solids?

-Gas-gas solutions form readily because all gases are miscible with each other -A gas may dissolve in a solid by occupying the spaces between the solid particles -Gas-solid solutions are important as catalysts

An alcohol possesses a ____________ hydroxyl (-OH) group and a ______________ hydrocarbon chain. Due to its _____________ polarity, an alcohol is able to dissolove in both polar and nonpolar solvents.

-Polar -Nonpolar -Dual

Which of the following statements correctly describe the effect of alcohol structure on solubility?

-Smaller alcohols are more soluble in H2O than larger alcohols -As the hydrocarbon chain increases in length, the alcohol becomes less soluble in polar solvents.

Which of the following statements correctly describe the vapor pressure of a solution containing a volatile nonelectrolyte solute?

-The vapor pressure of each volatile component can still be calculated using Pa=XaP*a -The vapor pressure of both volatile components will be lowered -The quantity of the volatile component in the vapor will be greater than that in the solution.

If more solute is added to a solvent, more than is able to dissolve at a given temperature, a ____________ will be established between dissolved and undissolved solute. The rate at which solute continues to dissolve is ____________ to/than the rate at which solute crystallizes from solution.

-equilibrium -equal

Most strong electrolyte solutions are not ideal so that the measured value of the van't Hoff factor i is _____________ than expected from the formula of the compound. This is because ions in solution are not totally isolated from each other, but remain clustered together to form an ionic atmosphere. This ______________ the effective concentration of particles and therefore the measured value of i.

-lower -decreases

A solution containing a nonvolatile solute will have a _________________ vapor pressure than the pure solvent. The change in vapor pressure is proportional to the _____________________ fraction of the solute in the solution.

-lower -mole

Solubility is defined as the ____________amount of solute that is able to dissolve in a fixed amount of a particular solvent at a particular ____________ and pressure.

-maximum -temperature

Most solids are _________ soluble in a particular solvent at higher temperatures than at lower temperatures, although there are some exceptions. The solubility of a gas in water will generally ___________ as temperature increases.

-more -decrease

Calculate the expected boiling point of a solution containing 0.72 mol of MgCl2 in 1.00 kg of H2O if Kb=0.512*CxKg/mol

100*C +(2.16 x 0.512)= 101.1*C MgCl2 dissociates to form three ions, so 1=3 and the molality is 2.16 mol/kg

What mass of CCl4 is required to prepare a 0.25 m solution using 115g of hexane? (molar mass of CCl4=153.81g/mol and molar mass of hexane=86.17g/mol

4.42g 0.115kg hexane x (0.25mol CCl4/1kg hexane)x (153.81g CCl4/1 mol CCl4) = 4.42g CCl4

Unsaturated solutions

Contain less than the equilibrium concentration of dissolved solute; more solute added will dissolve.

Supersaturated solutions

Contain more than the equilibrium concentration of solute; the solution is unstable and solute will separate from it readily.

Saturated solutions

Contain the maximum amount of dissolved solute; more solute added will not dissolve

How does the presence of a strong electrolyte in solution affect the colligative properties of a solution when compared to the same number of moles of a nonelectrolyte solute?

The electrolyte dissociates or ionizes to give a larger number of moles of dissolved particles, with a greater effect on the colligative properties.