Propiedades y Estados Físicos

Solutions, Solubility, and Colligative Properties

por Robin Marks, M.A., Anthony Carpi, Ph.D.

A solution is _____.
- a.a liquid mixture that must be predominantly water
- b.a liquid mixture that is predominantly solvent
- c.a liquid mixture that is predominantly solute
- d.a liquid mixture that contains a solid
In a solution containing water and polar solute particles _____.
- a.the polar particles will disperse randomly throughout the water
- b.the polar particles form ionic bonds with water molecules
- c.the polar particles will not dissolve
- d.hydrogen bonding allows the particles to dissolve
In a polar solution, the solute particles become dissolved when intermolecular forces cause solvent particles to surround them.
- a.true
- b.false
Which of the following is true about a nonpolar solution?
- a.There are no intermolecular forces at work.
- b.Nonpolar liquids generally do not form solutions with any other liquids.
- c.Hydrogen bonds are not at work in a nonpolar solution.
- d.Particles dissolved in a nonpolar solvent are not surrounded by solvent molecules.
You dissolve a polar compound into water and measure the temperature before and after. The temperature has increased. This tells you:
- a.You had to heat the water to get the compound to dissolve.
- b.The polar compound was initially at a higher temperature than the water.
- c.The new bonds that formed during the dissolution released more energy than was initially used to separate particles of the compound.
- d.New bonds were formed during the dissolution but no bonds needed to be broken.
Molarity tells us _____.
- a.how many grams of solute are dissolved in a given volume of solution
- b.how many particles are dissolved in a given volume of solution
- c.the likelihood that a given volume of solution will dissolve more solid
- d.whether a solution is considered weak or strong
You have 15g of sodium iodide (NaI), which has a molecular weight of 150 g/mol. You place it all in a beaker and fill the beaker to until you have one liter of solution. What is the molarity of the solution?
- a.15M
- b.0.15M
- c.0.1M
- d.0.01M

You have a solution of sodium iodide (NaI) and need to add something to it that will precipitate the iodine ions out while leaving the sodium ions in solution. According to the solubility chart below, which of these compounds would accomplish that?

**Table 1:** Solubility rules for soluble ionic compounds in water
Compounds containing:	Exceptions:
NO₃^-	n/a
C₂H₃O₂^-	n/a
CL^-	Ag⁺, Hg₂²⁺, & Pb²⁺ compounds
Br^-	Ag⁺, Hg₂²⁺, & Pb²⁺ compounds
I^-	Ag⁺, Hg₂²⁺, & Pb²⁺ compounds
SO₄^2-	Sr²⁺, Ba²⁺, Hg₂²⁺, & Pb²⁺ compounds

**Table 2:** Solubility rules for insoluble ionic compounds in water
Compounds containing:	Exceptions:
S^2-	NH₄⁺ compounds, alkali metal cations, Ca²⁺, Sr²⁺, & Ba²⁺
CO₃^2-	NH₄⁺ compounds & alkali metal cations
PO₄^3-	NH₄⁺ compounds & alkali metal cations
OH^-	Alkali metal cations compounds, NH₄⁺, Ca²⁺, Sr²⁺, & Ba²⁺

a.Silver nitrate (AgNO₃)
b.Aluminum nitrate (Al₃NO₃)
c.Sodium nitrate (NaNO₃)
d.Sodium phosphate (Na₃PO₄)

Colligative properties arise from the fact that solute affects the concentration of solvent.
- a.true
- b.false
By adding antifreeze to the water in the radiator of a car, you:
- a.Lower the freezing point of water in the radiator
- b.Raise the boiling point of water in the radiator
- c.Lower the concentration of water in the radiator
- d.All of the above

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