Solubility & Concentrations Practice Quiz

Distinguish between an alloy and amalgam. Give one example of each.

Answer explanation

An alloy is a solid solution of metals (e.g. copper-nickel alloys to make coins).

An amalgam is an alloy that is made of metal dissolved in mercury (e.g. dental filings)

Describe the effect of increasing temperature on the solubility of:

a. A typical solid in water.

b. A gas in water

Answer explanation

Solids - as temperature increases, solubility increases.

Gases - as temperature increases, solubility decreases.

Using the solubility curve graph:

a. which substance's solubility is LEAST changed as the temperature is increased?

b. based on the characteristics of gases, liquids, and solids, predict which solute is MOST likely a gas. Explain how you know this.

c. How many grams of solute A can be completely dissolved in 200 grams of water at 90 degrees Celsius to make a saturated solution.

Answer explanation

A. B

B. D because as the temperature is increasing, the solubility is decreasing.

C. 128g

60mL of ethanol is diluted with water to a final volume of 400mL. What is the percent by volume of ethanol in the solution?

Answer explanation

15%

A standard solution of 0.250mol/L calcium carbonate is prepared by dissolving solid calcium carbonate, CaCO3, in an acid. What mass of calcium carbonate is needed to prepare 1.00L of this solution?

Answer explanation

25.02g

A 2.25mg sample of dioctyl phthalate (C24H38O4), a plasticizer, is dissolved in H2O to give 530mL of solution. What is the concentration of dioctyl phthalate in ppb?

Answer explanation

4245.3micrograms/L

What mass of solute is present in 500mL of 0.10mol/L AgNO3?

Answer explanation

8.49g

Why did the white bear dissolve in water?