Before the Bell Rings New Seats! Grab 1 Paper from the side table One person in each two person group log onto the computer at your table. Have your “Like Dissolves Like” WS out to check.

ETD#46 1. Solute(s) 2. Solvent(s) 3. Solution(s) In a pitcher of Kool-aid, what is/are the: 1. Solute(s) 2. Solvent(s) 3. Solution(s) How can you tell if the solution is saturated with sugar?

ETD#46ANS Solute – thing being dissolved (sugar, Kool-Aid) Solvent – thing doing the dissolving (water) Solution – homogenous mixture of the solute plus solvent Saturated – no more sugar dissolves.

Learning Targets I can use scientific vocabulary to correctly describe solutions.

Polar vs Non-Polar: How do you know? Quick Way: Just C & H: Non-Polar. Ex: C3H8, CH4 Just one Element: Non-Polar. Ex: O2, H2 H’s and O’s (or H’s and N’s): Polar Ex: C6H12O6, H2O, NH3 More Accurate Way: Draw the Lewis Dot Structure. Tetrahedral / linear = non-polar Ex: CH4 , CO2 Bent / trigonal pyramidal = polar Ex: H2O, NH3

Factors that affect the rate of dissolving Expose greater surface area Stir Heat Polarity Why do each of these affect the rate of dissolving?

Dissociating = Breaking into Ions

Soluble vs. “Insoluble” NOTES Soluble vs. “Insoluble” Soluble = Dissolvable Easily Dissolves in Water. Likes Water More Than Other compds Will NOT form a precipitate More Attracted to water “Insoluble” = Partially Soluble Barely Dissolves in Water, Likes Water less than other compds. Forms a precipitate Less attracted to water

Salt Dissociating

Qualitatively describing the concentration of a solution … Unsaturated - more solute can be dissolved in the solution Saturated – no more solute can be dissolved in solution

Supersaturated A solution that contains more dissolved solute than it should at a temperature (very unstable – will become saturated if there’s something to connect around) http://www.youtube.com/watch?v=nvHrXr5Jaj g http://www.youtube.com/watch?v=omezbP7Rm pk ***SAVE UNTIL TEMP / SATURATION NEXT YEAR?*** 3.5 g of Sodium Acetate * 3H2O per mL used. e.g. 175 g / 50 ml Or 105 g / 35 ml Neil: 50g / 5 mL

PhET – Soluble Salts Go to the site on the handout. Work with your elbow partner. There are words you may not know on the handout. Look them up online. Look them up in a chem book.

What didn’t the model show?

Why does salt easily dissolve in water? What doesn’t PhET Show? Why does salt easily dissolve in water? Water and Salt are both “polar” and attracted to one another Like Dissolves Like! H2O goes in the “spaces” and “dissolves” the NaCl into ions Na+ and Cl-Ions Dissociate and stay surrounded by water. http://www.mpcfaculty.net/mark_bishop/NaCl_dissolves.htm How is this different for polar and non-polar molecules?

Learning that vocab…

Learning Targets I can use scientific vocabulary to correctly describe solutions.

Homework 1. Phet Salts and Solubility- Due next class.