Solutions Solubility Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings
Solubility Solubility is the maximum amount of solute that dissolves in a specific amount of solvent. expressed as grams of solute in 100 grams of solvent water. g of solute 100 g water
Unsaturated Solutions contain less than the maximum amount of solute. can dissolve more solute. Dissolved solute Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings
Saturated Solutions Saturated solutions contain the maximum amount of solute that can dissolve. have undissolved solute at the bottom of the container. Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings
Supersaturated Solutions An unstable solution that contains an amount of solute greater than the solute solubility. Also has undissolved solute at the bottom of the container. Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings
Effect of Temperature on Solubility Depends on temperature. Of most solids increases as temperature increases. Of gases decreases as temperature increases.
WHAT DO THESE GRAPHS MEAN? Each line shows how much stuff (SOLUTE) can be dissolved in 100 mL OF WATER (SOLVENT) at different temperatures. Why at different temperatures? Hot dissolves a solute faster and also dissolve a GREATER MASS of solute, in the same volume of water.
The LINE ITSELF also represents a Saturated solution; that is, a solution with the EXACT amount of solute that will saturate 100 mL of water:
At any temperature, any LESS solute than the value on the line would produce an UNSATURATED solution (points below the line ) If 5 grams of mix were added to 40o water, the solution would not be saturated, as shown by the point BELOW the saturation line
At any temperature, any MORE solute than the value on the line would produce an OVERSATURATED solution (points above the line) If 70 grams of mix were added to 100o water, the solution would be more than saturated, as shown by the point ABOVE the saturation line
SOLUBILITY GRAPH OF SALTS IN WATER CHEMISTRY RESOURCE 9C SOLUBILITY GRAPH OF SALTS IN WATER M.ALI. BLL, 2008
SOLUBILITY GRAPH OF GASES IN WATER Pressure has little effect on the solubility of liquids and solids. The solubility of gases is strongly influenced by pressure. Gases dissolve more at high pressure.
Learning Check A. Why could a bottle of carbonated drink possibly burst (explode) when it is left out in the hot sun ? B. Why do fish die in water that is too warm?
Learning Check At 40C, the solubility of KBr is 80 g/100 g H2O. Identify the following solutions as either 1) saturated or (2) unsaturated. Explain. A. 60 g KBr added to 100 g of water at 40C. B. 200 g KBr added to 200 g of water at 40C. C. 25 g KBr added to 50 g of water at 40C.
Solution 2 Amount of 60 g KBr/100 g water is less than the solubility of 80 g KBr/100 g water. 1 In 100 g of water, 100 g KBr exceeds the solubility of 80 g KBr water at 40C. C. 2 This is the same as 50 g KBr in 100 g of water, which is less than the solubility of 80 g KBr/100 g water at 40C.
Solution A. The pressure in a bottle increases as the gas leaves solution as it becomes less soluble at high temperatures. As pressure increases, the bottle could burst. B. Because O2 gas is less soluble in warm water, fish cannot obtain the amount of O2 required for their survival.