Mix and flow of matter
The Many Uses of Fluids
Anything that has no fixed shape and can flow (usually a gas or liquid); takes the shape of its container.
Fluids Make it Easier to Use Materials
- A slurry is a mixture of water and solids ( ex. Dirt and water). It is a form of a fluid.
- Used in mining oil sands
- Some solids are originally prepared as fluids (ex. Glass or steel).
- Fluids have the ability to spread or flow and carry other materials.
- Toothpaste contains powdered material, detergent, fluoride, binders, coloring, and flavoring
Useful Properties of Fluids
- Fluids are involved in transporting, processing, and using materials.
- Fluids can be used un different ways because of their properties
- By understanding the properties of fluids, people can design technological devices that use these properties
Recall from grade 7 of classifying matter:
Keeps its shape and keeps its total volume
Takes the shape of the container and keeps its total volume
Takes the shape of its container and changes volume to fill its container
Pure Substances & Mixtures
Matter is divided up into two classifications
Pure Substances :
Made of only one kind of matter; cannot be separated into different substances. Ex. Gold, aluminum foil
Made up of combination of different substances in which the different substances are easy to see. Ex. Soil, cake
Mixtures can be broken up even further!
Mechanical mixture :
A mixture that you can see different substances that make up the mixture. Also called a heterogeneous mixture.
Soil, mixed vegetables
A mixture of 2 or more pure substances that looks like one substance. Also called a homogenous mixture.
Pepsi, Copper Sulfate, Mio
A cloudy mixture in which droplets or tiny pieces of one substance is held within another substance; if left undisturbed, its parts will usually separate out. The particles settle slowly after mixing.
Muddy water, tomato juice, orange juice, salad dressing
A cloudy mixture in which droplets or tiny particles are too small to separate out, thus particles do not settle at all
Homogenized milk is a colloid of tiny cream droplets in whey, fog.
How can we figure out if something is a pure substance or solutions?
- Paper chromatography can be used to determine if fluids are pure substances or solutions.
- Filter paper is put in solution.
- Pure substance- fluid travels up one level
- Solution - fluid travels up many level
Concentration & Solubility
Dissolving one substance into another creates a solution
A substance that dissolves a solute to form a solution(ex. Water, known as the 'universal solvent').
A substance that dissolves in a solvent to form a solution.
The amount of solute (g or kg) dissolved in a specific amount of solvent (mL or L) in a solution; written as g/mL or kg/L. Means amount of solute/amount of solvent.
We use terms like 'concentrated' and 'diluted' to describe the solutions.
- In a concentrated solution there are large amounts of solute in a solution
- In a diluted solution there are small amounts of solute in a solution
Different types of concentrations
- Parts per million (PPM) - Very small amount
- Parts per billion (PPB) - Very very small amount
To compare concentrations, the volumes must be equal:
- Ex. 25g/100mL compared to 10g/50mL (Yay math!!)
- Must be changed to 25g/100mL compared to 20g/100mL so the volumes are equal.
Saturated and Unsaturated Solutions
Unsaturated Solution :
A solution in which more solute can be dissolved at a given temperature
Saturated Solution :
A solution in which NO more solute can be dissolved at a given temperature
- Solutions do not have to be made up of only liquids (see. P. 29) (example: carbonated pop)
What happens if you add more solute to an unsaturated Solution?
- Comes to a point where it becomes saturated
- If you change the pressure, volume or temperature, it can become ‘super saturated’
The ability to dissolve; the mass of solute that can dissolve in a given amount at a given temperature.
Saturation Point :
The point at which NO more solute can be dissolved at a certain temperature (ex. See pg 28).
Factors Affecting Solubility
Solubility depends on 3 factors.
- Type of solvent
- Type of solute
Aqueous Solution :
When water is the solvent in the solution. Water is sometimes referred to as the “universal solvent” because it can dissolve so many things.
Solubility Changes with Temperature
- For most substances, solubility increases as the temperature of the solvent increases
- Ex. at 25 degrees Salt- 36.2g/100ml water is saturated
- Ex. at 100 degrees Salt- 39.2g/100ml water is saturated
- Decrease in solubility of gases have a serious effect on the environment
- Water drawn from a lake as a coolant. When it goes back to the lake and it is not treated, it is warmer than it left
The Particle Model of Matter and the Behaviour of Mixtures
- Ancient Greek Democritus said all matter was made of small, invisible, indivisible particles
- Nobody believed him for 2000 years!
- 1808- John Dalton believes him and makes his atomic theory
Particle Model of Matter :
A model that explains the behaviour of solids, liquids, and gases; it states that all matter is made up of tiny moving particles that attract each other and have spaces between them.
Four Main Points of the Particle Model of Matter:
1. All matter is made up of tiny particles.
- Different substances are made up of different particles.
- There are more particles in a given volume of solid than there are in the same volume of liquid or gas.
- How big is a particle? In one snowflake there are 1018 particles.
2. The tiny particles are always moving and vibrating.
- For solids, the particles vibrate in one place.
- For liquids, the particles slide around and over each other.
- For gases – the particles move as far as the space they are in allows.
3. The particles in matter maybe attracted to each other or bonded together.
- Some particle (like water) have more attraction to particles than others (like salt).
4. The particles have space between them.
- Think like marbles & sand.
How the Particle Model Explains Mixing Substances.
- If the 2 substances with different size particles are mixed together, the smaller particles will fill spaces between the larger particles.
- The attraction of particles helps in dissolving.
3 factors affect how quickly a solute will dissolve in a solvent:
- Temperature – increasing the temperature causes the particles to move faster and bump into the solute particles faster.
- Surface Area – small pieces of solute dissolve more quickly than large pieces because there is a greater surface area where the solvent can make contact.
- Stirring – moves all the particles around, so the solvent particles bump into the solute particles.