Aim 1: Why don’t water and oil mix?

“Like Dissolves Like”Data:

NaCl will dissolve in water, but not oil.

I2 will dissolve in oil, but not water.

Sugar will dissolve in water, but not oil.

Hexane will mix with oil but not water.

Soap will mix with water and oil.

Data Analysis

Will dissolve in Water

Will dissolve in Oil

Dissolves in Water Dissolves in Oil Dissolves in Both

Salt --- ---

--- I2 ---

Sugar --- ---

--- Hexane ---

Vinegar --- ---

Soap Soap Soap

Dissolving Rules:1. 2.3.

Exit Ticket

What kind of substance would be needed to clean up an oil spill in the ocean?

Or

If our bodies are mostly water, how do we mix with the oils we eat?

Aim 2: Why do we put salt on the roads in winter?

Lesson Objectives: 1) Students should understand the effect of solutes on the boiling and freezing points of water.

2) Students should understand the relationship between the number of ions and the change in bp and fp. 3) Students should be able to determine the relative effect on bp and fp by determining the number of moles of particles produced when various compounds dissolve in water.

Why do we put salt in the water to boil spaghetti?

http://group.chem.iastate.edu/Greenbowe/sections/projectfolder/flashfiles/thermochem/solutionSalt.html

Colligative Properties

Properties that are affected by the

amount of particles present.

Number of Particles

Aff

ect

on P

rope

rty

Boiling Point Elevation and Freezing Point Depression

• Boiling Point of Water = ______________

• Freezing Point of Water = _____________

• Adding solutes to water will __________________ boiling point and __________________ freezing point.

• The greater the concentration of ions (moles of ions), the _____________ the bp and the _____________ the fp.

Which of these salts would you purchase to melt the ice on your

sidewalks?

CaCl250 lb bag$20.00

NaCl50 lb bag$20.00

Place the following in order of greatest change to bp/fp of water.NaCl(s)

MgCl2(s)

C6H12O6(s)

NH4NO3(s)

Ca3(PO4)2(s)

H3PO4(l)

Exit Ticket

Why would we add salt to ice used in making ice cream?