Solubility CurvesSolubility Curves

The amount of a solute that The amount of a solute that will dissolve is a solvent will dissolve is a solvent

depends upon the depends upon the temperature of the solution.temperature of the solution.

KNOKNO33 dissolved in water dissolved in water

• The data to the The data to the right is how many right is how many grams of KNOgrams of KNO33 solid that will solid that will dissolve in 100ml dissolve in 100ml of water at of water at different different temperatures.temperatures.

TemperatureTemperatureMass Mass

00ooCC 15g15g

1010ooCC 23g23g

2020ooCC 34g34g

3030ooCC 47g47g

3838ooCC 60g60g

KNOKNO33 dissolved in water dissolved in water

This graphs shows the relationship between how much solid potassium nitrate will dissolve in water at different temperatures. Notice how it is not a straight line, but curves upward. The hotter the water, the more potassium nitrate will dissolve.

Question?Question?

How much PotassiumHow much Potassium

Nitrate will dissolve Nitrate will dissolve atat

25 degrees Celsius?25 degrees Celsius?

Follow the line upFollow the line up

from 25 degrees andfrom 25 degrees and

then over to the then over to the

mass.mass.

Solubility Curve of NHSolubility Curve of NH33

Notice how the Notice how the curve is different curve is different from the solid from the solid potassium nitrate. potassium nitrate. The reason is The reason is simple, ammonia simple, ammonia (NH(NH33) is a gas. ) is a gas. Therefore it is Therefore it is less less soluble in hot soluble in hot water.water.

Saturated SolutionSaturated Solution

Any point on the line Any point on the line

indicates a indicates a saturatedsaturated

solution. Saturatedsolution. Saturated

means the solventmeans the solvent

has dissolved as has dissolved as

much solute as much solute as

possible. possible.

Unsaturated SolutionUnsaturated Solution

• The The red red area ofarea of

the graph the graph

represents an represents an

unsaturated unsaturated

solution. Less solution. Less

solute is dissolvedsolute is dissolved

than a saturated than a saturated

solution.solution.

Supersaturated SolutionSupersaturated Solution

• The The red red area ofarea of

the graph the graph

represents a represents a

supersaturated supersaturated

solution. More solution. More

solute is dissolvedsolute is dissolved

than a saturated than a saturated

solution.solution.

Use this graph to help you Use this graph to help you answer the rest of the answer the rest of the

questions.questions.