Solutions and Solubility Review Lesson

Hotspot

Which of the following solutions are heterogenous?

Match

Identify a solute, the solvent, and the solution in a carbonated drink (like soda).​

• Carbon Dioxide (dissolved in the drink)

• Water

• The Carbonated Drink

Solute

Solvent

Solution

• Solute

• Solvent

• Solution

Multiple Choice

When McDonald's sweet tea is really sweet, did they add too much solute or solvent?

• too much solute

• too much solvent

Multiple Choice

How can we dilute the sweet tea?

• add more sugar (solute)

• add more water (solvent)

Factors affecting rate of solubility

rate of solubility - time taken for a substance to completely dissolve in another substance

Factors affecting rate of solubility

• Temperature

• Rate of strirring

• Size of solute

By crushing the solute to smaller pieces the amount of surface area for the solute to contact the solvent INCREASES.

The more solute/solvent interactions that occur the faster will be the rate of dissolution!

This is why Kool-aid is such a fine powder!

***Important to note that molecular bonds are NOT being broken, the molecules are just in smaller pieces.

Size of solute - explained

Open Ended

Write an explanation of WHY it will dissolve the most quickly using the terms "surface area", "solvent" and "solute"

Draw

Circle the seltzer that will dissolve the most quickly. Then, write an explanation of WHY it will dissolve the most quickly using the terms "surface area", "solvent" and "solute"

Agitation - Recap

Stirring or agitating a solution increases the amount of solute/solvent interactions mechanically.

Increasing solute/solvent interactions increases rate of dissolution.

This is why you stir the Kool-aid when you add it to the water.

Open Ended

Write a description about how agitation is effecting the rate of dissolution.

Temperature - Recap

• Increasing kinetic energy (energy of motion) increases the number of solute/solvent interactions.

• Increasing the number of solute/solvent interactions increases the rate of dissolution.

• AGAIN NOTE that for gases, they are actually more soluble in liquids at lower temperatures, because they boil out when the temperature is too high.

Draw

Circle the container with the most kinetic energy. Then, write a description about the effect of increasing kinetic energy on the rate of dissolution.

Multiple Choice

Which of the following can increase the dissolving rate of a substance the most?

• mixing

• freezing

• heating it up

• adding more substance.

Match

Match the following terms:

• Increasing agitation

• Crushing solute

• Temperature increase

Mechanically increases number of solute/solvent interactions to increase rate of dissolution

Increases surface area of solute to interact with solvent to increase the rate of dissolution

Increases kinetic energy of solute and solvent particles to increase rate of dissolution

• Mechanically increases number of solute/solvent interactions to increase rate of dissolution

• Increases surface area of solute to interact with solvent to increase the rate of dissolution

• Increases kinetic energy of solute and solvent particles to increase rate of dissolution

Multiple Choice

Which is not a factor affecting solubility?

• Agitating (mixing, stirring, shaking) the mixture

• Increasing the surface area of the mixture

• Increasing the volume of the mixture

• Increasing the temperature of the mixture

Multiple Choice

When 42 grams of potassium chloride, is dissolved in 100 grams of water at 50 ºC, the solution can be correctly described as:

• supersaturated

• saturated

• unsaturated

Multiple Choice

When 50 grams of KCl is dissolved in 100 grams of water at 50 ºC, the solution can be correctly described as:

• supersaturated

• unsaturated

• saturated

Multiple Choice

When 20 grams of potassium chlorate, KClO₃, is dissolved in 100 grams of water at 80 ºC, the solution can be correctly described as:

• supersaturated

• saturated

• unsaturated

Multiple Choice

Which solute is the least soluble at 90 ⁰C?

• SO₂

• KClO₃

• KI

• HCl

Multiple Choice

Which solute is the most soluble at 10 ⁰C?

• KI

• KClO₃

• NH₄Cl

• NH₃

Multiple Choice

Which substance is MOST soluble at 0 ºC?

• KI

• NaNO₃

• NaCl

• Ce₂(SO₄)₃

Multiple Choice

How many grams of K₂Cr₂O₇, are soluble in 100 g of water at 90 ºC?

• 85 grams

• 70 grams

• 40 grams

• 15 grams

Multiple Choice

25 grams of NaCl are dissolved in 100 mL of water at 60 C. How many more grams need to be dissolved for the solution to be saturated?

• 13 grams

• 25 grams

• 6 grams

• 38 grams

Multiple Choice

At approximately what temperature does the solubility of sodium chloride, NaCl, match the solubility of potassium dichromate, K₂Cr₂O₇?

• 60 ºC

• 30 ºC

• 50 ºC

• 83 ºC

Multiple Choice

At approximately what temperature does the solubility of sodium chloride, NaCl, match the solubility of potassium dichromate, K₂Cr₂O₇?

• 60 ºC

• 30 ºC

• 50 ºC

• 83 ºC