IPC 9.B Relate the concentration of ions in a solution to physical and chemical properties such as...

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IPC 9.BRelate the concentration of ions in

a solution to physical and chemical properties such as pH,

electrolytic behavior, and reactivity.

• In the example above, the salt (NaCl) separates into ions which become dissolved in the water.

• The polar nature of water molecules allows them to easily pull ions into solution.

Ions in solution can change the properties of the solution.

Electrolyte – with ions

Conducts electricity

Non-electrolyte – without ions

Does not conduct electricity

A BASE is any chemical substance that produces and

donates a hydroxide ion (OH-)

into the solution

An ACID is any chemical substance that produces and donates hydrogen ions (H+) into the

solution

Sometimes a Basic

substance is said to be alkaline.

pH measures H+ ions in solution

High H+ Concentration

Low OH- Concentration

Low H+ Concentration

High OH- Concentration

Equal H+ and OH-

IPC 9.DDemonstrate how various factors

influence solubility including temperature, pressure, and nature of

the solute and solvent

All of these can affect the rate at which a solid dissolves in water except —

A decreasing air pressure

B stirring the water

C increasing the temperature of the water

D using larger crystals of the solid

A 0.2 g crystal of gypsum dissolves very slowly in 100 mL of water while the water is stirred. Which of these would cause the gypsum to dissolve faster?

F Decreasing the water temperature

G Stopping the stirring

H Lowering the air pressure

J Crushing the crystal

What are the 3 ways to increase the rate at

which a solid dissolves?

Heat it!

Crush it!

Stir it!

ANSWER?

J

How much solute will dissolve?

• A solubility curve shows the amount of each solute that will dissolve in 100g H20 at each temperature.

• Saturated is on the line. • Unsaturated is below the

line. • Supersaturated is above the

line.

At which temperature do KBr and KNO3 have the same solubility?

A 27°C

B 48°C

C 65°C

D 80°C

Pressure and Solubility of Gasses

• The higher the pressure above a liquid, the more gas can be dissolved in the liquid.

Try this one!

49 According to the graph, about how muchhemoglobin would be saturated at an O2pressure of 7.3 kPa?A 32%B 67%C 89%D 92%

You can dissolve

more gas in a cold liquid than a hot

liquid!