1. Topic 2: Properties of Fluids

2. What is a Fluid? Anything that flows Has no fixed shaped Examples?
Liquid or gas
Examples?

3. Why care about fluids?

4. Your bicycle starts to make grinding noises as you pedal
Your bicycle starts to make grinding noises as you pedal. What do you do?
You are dehydrated from working out in the sun all day. What do you do?
You are building a ship that needs to sail across the Atlantic Ocean. How do you know your ship will float?
You are making caramel; how do you know when you have added enough sugar?
You are working at a construction site and need to break apart some concrete. How do you do it?

5. Fluids make it easier to transport, process and use different kinds of materials
Non-fluid materials can be behave like fluids if they are melted or dissolved
Fluids can do work
When they move, they do so with a force

6. Properties of Fluids

7. Solubility What makes a substance dissolve?
Occurs because of the attraction between the different particles
2 parts to a solution:
Solute
The substance that dissolves
Ex. In saltwater, the salt is the solute
Solvent
The substance that does the dissolving
Ex. In saltwater, the water is the solvent

8. Solubility in g/100mL of Water @ 0°C
Solubility is the maximum amount of a solute you can add to a fixed volume of solvent at a given temperature
Creates a saturated solution
No more solute is able to dissolve
Solubility in g/100mL of 0°C
Salt
35.7
Baking soda
6.9
Carbon dioxide
0.35
Sugar
180
Hydrogen
Oxygen
0.007
Ammonia 92

9. Solubility is not a static property
It can be manipulated
What are some factors that you think will affect the rate of solubility of a substance?

10. Laboratory Activity 2: Manipulating Solubility
Each group will investigate one factor that affects solubility
Temperature
Surface area
Agitation
Type of solute
Type of solvent
Groups will design and conduct an investigation and then share their findings with the class

11. Solubility & Particle Model
How can we explain solubility in terms of particles?
When 2 substances are mixed together, their particles interact
If the substance is SOLUBLE...
Particles of solute are attracted to the particles of the solvent are attracted to each other
Solute dissolves in the solvent

12. Particles of solute are repelled by particles of solvent
If the substance is INSOLUBLE...
Particles of solute are repelled by particles of solvent
Form distinct layers

13. Effect of Temperature Increases number of collisions between particles
Increasing the temperature makes the particles move faster
Increases number of collisions between particles
Solute dissolves faster

14. Surface Area
Smaller pieces have more surface area for the solvent particles to bump into
Solute dissolves faster

15. Agitation Moves the particles around
Increases the number of collisions between particles
Solute dissolves faster

16. Type of solute / solvent
Some particles have charges
Polar molecules
When mixed together, the charges interact
Particles that have charges don’t like to mix with particles that don’t have charges (non-polar)