Osmosis and DiffusionGummy Bear Lab

Diffusion

• SOLUTE PARTICLES move from HIGH concentration to LOW concentration.

HIGH CONCENTRATION

LOW CONCENTRATION

Osmosis

• Diffusion of WATER across a membrane.• Water follows the solute particles.

“SOLUTE SUCKS!”

Gummy Bears, Day 1

• A gummy bear, full of SUGAR SOLUTE, is placed in water.

• Where does the water want to go?– To the solute! The solute “sucks”

the water towards it.

Water follows solute!

So now your gummy looks like this:

After sitting in a glass of water

Normal size

Gummy Bears, Day 2

• A gummy bear, full of water and sugar solute, is placed in a cup of fresh water.

• What happens? – Since the gummy still contains more solute (sugar)

inside, the water does not flow in or out of the gummy bear.

Gummy Bear, Day 2

• A gummy bear, full of water and sugar, is placed in a cup full of concentrated salt water.

• Where does the water want to go?– Since the salt water was much more concentrated,

the water now flows from the gummy bear to the water. “SOLUTE SUCKS!”

Water will go where there is more concentrated solute! “SOLUTE SUCKS!”

After sitting in concentrated salt water:

He has lost all of his excess water to the high salt concentration in the outside water!

Law of Conservation of Mass

Matter or Mass cannot be created, lost, or destroyed.

The reactants = the products

This is why we must balance equations!

Lab Station #1- Baking soda + VinegarSubstance Mass

Vinegar (reactant) 11.0g

Baking soda (reactant) + 2.5g

Theoretical mass of products= =13.5g

Solid baking soda + vinegar after reacting

(total product)

13.0g

How much was lost as a gas????

13.5-13.0=0.5g (amount of product escaped as

a gas!!)

Lab Station #1- What happened?

Vinegar(11.0g)

REACTANTS = 13.5g

PRODUCTS=13.5g

Vinegar + Baking Soda (13.0g)

2.5g

Gas (0.5g)

Station #2-Balancing Equations

All chemical reactions must satisfy, or meet the Law of Conservation of Mass!!!

We must balance all of the atoms on each side of the reaction.

Example:2 C2H6(g) + 7 O2(g) 4 CO2(g) + 6 H2O(g)

Mg(s) + O2 (g) → MgO(s)

Fe2O3 + CO 2Fe + CO2