Science 8. Unit A - Mix and Flow of Matter. Topic 1: Matter on the Move

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1 Science 8 Unit A - Mix and Flow of Matter Topic 1: Matter on the Move 1. Investigate and describe fluids used in technological devices and everyday materials. 1C. Describe examples in which materials are prepared as fluids in order to facilitate transport, processing or use (e.g., converting mineral ores to liquids or slurries to facilitate transport, use of paint solvents to facilitate mixing and application of pigments, use of soapy water to carry away unwanted particles of material). 1D. Identify properties of fluids that are important in their selection and use (e.g., lubricant properties of oils, compressibility of gases used in tires).

2 Topic 1 - Matter on the Move The Particle Model of Matter 1. All substances are made of tiny particles. 2. All particles in a pure substance are the same. Different pure substances are made of different particles. 3. The particles have spaces between them. 4. The particles are always in motion: vibrating, rotating, and (in liquids and gases) moving from place to place. The speed of the particles increases/decreases when the temperature increases/ decreases. 5. The particles in a substance are attracted to one another. The strength of the attractive force depends on the type of particle. Volume Shape Example Solid Definite Definite Sugar cube Liquid Definite Not Definite Water Gas Not DefiniteNot Definite Oxygen Particles in Solids - Particles are tightly packed together and cannot move from each other. - There are small spaces between each particle too small to see. Particles in Liquids - Particles in liquids have enough energy to pull away from each other. - Liquids move by all the particles moving together, but not with each other. As a result they take on the shape of the object (container) they are in. Particles in Gases - There are large amounts of space between each particle. - Gas particles will spread apart if given the chance. - Gases take on the shape of the object (container) they are in.

3 Make sure you understand this diagram!! Page 10 Plasma Changes of State, read page Unit A: Mix and Flow of Matter Topic 2 - Mixing and Dissolving

Pure Substances Pure Substances: contain only one

Element: made from one type of atom (ex.

(NaCl, H 2 O) Mixture: contains two or more pure

to describe matter Homogeneous Mixtures Mixtures

properties -They are blended very thoroughly, so

amounts of matter that make up the mixture

4 Pure Substances Pure Substances: contain only one type of particle Example: gold, copper, oxygen gas Element: made from one type of atom (ex. gold, O 2 ) Compound: made from two or more atoms (NaCl, H 2 O) Mixture: contains two or more pure substances Properties: characteristics that help to describe matter Homogeneous Mixtures Mixtures that look like they have only one set of properties -They are blended very thoroughly, so that every part of the mixture contains equal amounts of matter that make up the mixture Example: Paint - Homogeneous means that every part of the mixture is the same. - A solution is a mixture of a homogeneous substance that does not settle. Example: A mixture of sugar and water

5 Heterogeneous Mixtures -A heterogeneous mixture contains two or more materials that are visible. - Heterogeneous means made up of parts or mixed. Example: granola bar, cookie dough, salad dressing, sand Mechanical Mixtures - Mixtures that are obviously heterogeneous are usually called mechanical mixtures - There are visible separate parts of the mixture that are called phases. Example: Oil and water, granola bar, sand, etc.

Other Mixtures Suspension: a heterogeneous mixture in which the

usually large enough to get trapped in most fine filters.

Mixtures Colloid: a heterogeneous mixture in which the particles

own and these particles are small enough to pass through most

6 Other Mixtures Suspension: a heterogeneous mixture in which the particles settle slowly after mixing Suspended particles are usually large enough to get trapped in most fine filters. Example: salad dressing, orange juice, clay and water Other Mixtures Colloid: a heterogeneous mixture in which the particles do not settle Example: milk - Usually do not separate on their own and these particles are small enough to pass through most filters - Homogenization is a process that helps to suspend fat globules in milk

7 Other Mixtures Emulsion: a mixture in which droplets of fat are prevented from joining together by an emulsifying agent Example: mayonnaise, peanut butter What Makes Materials Dissolve? Dissolving: a solution formed by mixing two or more materials. Example: Salt dissolves in water Dissolving is based on two points from the Particle Theory of Matter - Particles attract each other. - Particles are always moving.

If particles are attracted to each other, then they will blend in and appear to be dissolved. Example: Sugar and water attract, and the particles will blend together.

1 page 18 Solute: the substance that DISSOLVES IN a solvent to form a solution (does not settle). Example: - Salt is a solute that dissolves IN water.

8 If particles are attracted to each other, then they will blend in and appear to be dissolved. Example: Sugar and water attract, and the particles will blend together. If particles are not attracted to each other then they will be isolated in large chunks. Example: Oil and water do not mix, so the oil stays separated from the water. Solutes and Solvents Table 1.1 page 18 Solute: the substance that DISSOLVES IN a solvent to form a solution (does not settle). Example: - Salt is a solute that dissolves IN water. - Chocolate syrup is a solute that dissolves IN milk. Solvent: the substance that DISSOLVES a solute to form a solution. Example: - Water is a solvent that DISSOLVES salt. - Milk is a solvent that DISSOLVES chocolate syrup. Soluble: able to be dissolved into a substance. Example: - salt is soluble in water. - salt is soluble in orange juice. Insoluble: cannot be dissolved into a particular solvent Example: oil is insoluble in water

Water: the Universal Solvent Water is capable of dissolving

Consider the following: - 97% of water on earth is ocean

5% of water is usable for drinking The Rate of Dissolving

What might affect the rate of dissolving?

dissolve faster in the solvent - Temperature and pressure

9 Water: the Universal Solvent Water is capable of dissolving many substances. This ca be good and bad. Consider the following: - 97% of water on earth is ocean water - 2% of water is frozen in the Arctic and Antarct - 0.5% of water is usable for drinking The Rate of Dissolving Rate of Dissolving: how fast a solute dissolves in a solvent What might affect the rate of dissolving? Agitation:stirring or shaking which helps the solute dissolve faster in the solvent - Temperature and pressure are important factors that affect the rate of dissolving - A material will dissolve faster if it is in small pieces

in a given amount of solvent to form a saturated

Saturated solution: a solution in which no more

Unsaturated solution: more solute can dissolve into

Supersaturated solution: a solution that contains

10 How Much Can Be Dissolved? Solubility: the mass of a solute that can dissolve in a given amount of solvent to form a saturated solution - the limit! Saturated solution: a solution in which no more solute will dissolve at a certain temperature. Unsaturated solution: more solute can dissolve into a solution at a certain temperature. Supersaturated solution: a solution that contains more solute than would normally dissolve at a certain temperature. Unit A: Mix and Flow of Matter Topic 3: Separating Earth's Mixtures

11 How could you separate the following mixtures? Salt water Muddy water Nuts and bolts Iron filings and dirt Oil and sand Oil and water Salt and pepper Styrafoam and plastic blocks Pennies and dimes Wood chips and brick Separating Mixtures Picking Out With Tongs: This method is used to remove very large pieces of material from a mixture. For example, a pair of tongs can be used to pick out marbles from a small pile of sand. Magnetism: This method uses a magnet to remove any substance that is magnetic. For example, a magnet can be used to separate and remove thumbtacks from plastic paperclips.

Floatation: This method will separate materials that are less dense than the liquid. The materials that rise to the top can be scooped out with a spoon.

When mixed with water, the heavier particles will settle to the bottom.

Sifting: This method uses a sieve or strainer to separate the coarse parts from the finer material in a mixture.

12 Floatation: This method will separate materials that are less dense than the liquid. The materials that rise to the top can be scooped out with a spoon. For example, wood chips float on the surface of water. Settling (or Sedimentation): This method will separate out the heavier materials from the rest of a mixture. When mixed with water, the heavier particles will settle to the bottom. For example, when water is added to a mixture of gravel and sugar, the gravel settles to the bottom. Sifting: This method uses a sieve or strainer to separate the coarse parts from the finer material in a mixture. For example, flour for a cake is sifted to remove the coarse particles. Filtration: This method uses a filter paper to separate large particles from a mixture. The substance stopped by the filter paper is called the residue. The material that passes through the small holes is called the filtrate. For example, clay suspended in water can be separated from water by pouring the mixture through a filter paper.

Distillation: This method uses evaporation and condensation to recover the solvent in a solution.

13 Evaporation: This method is used to recover the solute in a solution by evaporating away the liquid portion of the solution. For example, salt can be recovered from salt water by evaporating the water. Distillation: This method uses evaporation and condensation to recover the solvent in a solution. The condensed substance that is collected is called the distillate. The substance that remains in the original container is called the residue. For example, distilled water can be recovered from ocean water by evaporating it, condensing the vapor, and collecting the product.

14 Processing Petroleum (page 30)

PURE SUBSTANCES VS. MIXTURES PENTONEY 2017

PURE SUBSTANCES VS. MIXTURES PENTONEY 2017 WHAT IS A PURE SUBSTANCE? Classification of matter that includes elements, molecules and compounds Cannot be separated by physical means such as distillation,