Fat Soluble – will NOT dissolve in water (will only dissolve in oils)
Vitamin A, K …
Can be ingested periodically, stored in body fat
B. Common ways to increase the rate of dissolving
1. Increase Temperature. Increasing the temperature adds more energy and creates more collisions of solute and solvent to help dissolve .
a. Ex: dissolving sugar in Warm tea vs. cold tea
2. Increase surface area.
Smaller pieces dissolve more quickly because there are more places to interact between solvent and solute.
Pulverize = crush or smash
a. Ex: Sugar packets vs. Sugar cubes
3. Increase movement (stirring).
By adding motion you add kinetic energy and move the solvent around to dissolve it.
a. Ex: Stirring the sugar into the tea vs. letting it dissolve on its own
C. Dissolving gases follow different rules
1. Gases dissolved in liquids prefer lower temperatures. Cold soda has more carbonation than warm sodas
2. Prefer less movement, more movement lets the gas escape more easily. Shaken sodas lose the dissolved gases quickly & so have fewer bubbles.
3. Increased Pressure increases rate of dissolving.
So when the bottle the soda they bottle it under higher pressure to keep the gas dissolved in it
Solids are more soluble at...
Gases are more soluble at...
low temperatures &
EX : nitrogen narcosis, the “bends,” soda
IV. Concentrations of solution – how “strong” or “weak” the solution is
A. 3 types of solutions based on concentration of dissolved solute
1. Unsaturated solution – Solution that can easily dissolve more of the solute does not require an increase in temperature to add more solute.
a. Ex. Weak sweet tea or unconcentrated acid.
2. Saturated solution – Solution that has the maximum amount of solute dissolved for that temperature.
Any change in temperature will affect the concentration.
3. Supersaturated solution – Solution that has a higher concentration of solute than it normally would at that temperature.
It was heated up, come out of solution.
Typically can’t be disturbed or it will crystallize.
Solubility increasing concentration SATURATED SOLUTION no more solute dissolves UNSATURATED SOLUTION more solute dissolves SUPERSATURATED SOLUTION becomes unstable, crystals form
B. Solubility Chart
1. Shows how the solubility changes at different temps
Solubility Table LeMay Jr, Beall, Robblee, Brower, Chemistry Connections to Our Changing World , 1996, page 517 0 10 20 30 40 50 60 70 80 90 100 Solubility vs. Temperature for Solids Solubility (grams of solute/100 g H 2 O) KI KCl 20 10 30 40 50 60 70 80 90 110 120 130 140 100 NaNO 3 KNO 3 HCl NH 4 Cl NH 3 NaCl KClO 3 SO 2
shows the dependence
of solubility on temperature
maximum grams of solute that will dissolve in 100 g of solvent at a given temperature
varies with temp
based on a saturated solution
Classify as unsaturated, saturated, or supersaturated per 100 g H 2 O 80 g NaNO 3 @ 30 o C unsaturated saturated unsaturated supersaturated 45 g KCl @ 60 o C 50 g NH 3 @ 10 o C 70 g NH 4 Cl @ 70 o C