Topic: Solubility and Table G Do Now: label as soluble and insoluble 1. CH 4 2. AgCl 3. C 12 H 22 O NaNO 3 5. KOH

Review: Next 3 slides

Water is often used as a solvent Soluble = dissolves in water = aq Insoluble = doesn’t dissolve in water Miscible = 2 liquids that dissolve Immiscible = 2 liquids that don’t dissolve Not everything dissolves in water

How can you tell….?!!!?? Like Dissolve Like – Water is polar, so most polar compounds will dissolve in water Things that dissolve in water – Soluble ionic compounds – use Table F – Acids - start with H except H 2 O H 2 O 2 ex HCl – Bases - metal + OH and NH 3 ex. NaOH – Polar covalent molecules Remember polar = asymmetrical = poles nonpolar = symmetrical = no poles

Determining if an ionic compound is soluble (aq) or NOT LOOK AT TABLE F – LiOH – Cu(NO 3 ) 2 – AgCl 2 – MgS – NaS 2 – KOH –aq –Insoluble = s –aq

Factors that affect the rate a species dissolves – Increasing temperature – stirring (agitation) – Crushing (smaller particle size) Solubility = the max amount of solute that can be dissolved in a solvent

Solubility Many solids and gases dissolve in water As you increase the temperature, you can dissolve more solid Does this work the same with gas? NOT the same for gases – as you increase temp, gas molecules KE ? To get gases dissolve, decrease temperature and increase pressure

DEMO VIDEO

Summary: Factors Affecting Solubility Nature of the solvent and the solute: Nature of the solvent and the solute: LIKE DISSOLVES LIKE Temperature Temperature Pressure (for systems with gases) Pressure (for systems with gases)

Solubility curves show the relationship between solubility and temperature. Can you guess which of these compounds are gases?! How do you know?!

Reading a solubility curve! Table G tells you the max amount of solute you can dissolve in 100 g of H 2 O at a given temperature

How much H 2 O is required to just dissolve 100 g NaNO 3 at 20  C? 89 g

How much KCl will dissolve in 100g of water at 50  C? Problem: 42 g

On the line – saturated (full, cannot hold any more solute Below the line – unsaturated (can hold more solute) Above the line – supersaturated (holding more solute then it should – very unstable)

Unsaturated solution

Saturated Solution

Supersaturated Solution (this picture is showing the addition of 100 g of glucose to 100ml of water at 25 0 C) Note: at 25 0 C, only 91g of glucose will dissolve in 100 ml of water Let’s see what happens Let’s see what happens