Mix and Flow Notes KEY (for Students) PDF

Unit 2: Mix and Flow What are fluids? What are they made of and how do we use them? What properties of fluids are important to their use? Topic 1 Matter On the Move I can identify the main points of the particle model of matter and explain them. I can label a change of state t...

Unit 2: Mix and Flow What are fluids? What are they made of and how do we use them? What properties of fluids are important to their use? Topic 1 Matter On the Move I can identify the main points of the particle model of matter and explain them. I can label a change of state triangle diagram and explain each term. I can compare and contrast the three main states of matter, solid, liquid and gas. I can explain what fluid is and know which states of matter are considered a fluid. 1 Topic 1 Vocab Gas Liquid Solid Condensation Plasma Fluid Matter Deposition Fusion Solidification Evaporation Sublimation States of Matter Questions 2 Properties of Fluids The three states of matter can be classified as being either a solid, a liquid or a gas. Solid: has a definite shape and definite volume. Liquid: has an undefined shape and definite volume. Gas: has an undefined shape and an undefined volume. Plasma 3 Properties of Fluids- What is a fluid? You can easily observe fluids such as water flowing out of a tap, milk or juice being poured into a glass, or ketchup oozing from a bottle. Your body contains many fluids, such as blood, water and cytoplasm inside cells. It is more difficult to imagine gases flowing, but they do. Take a deep breath. What happened? Some of the air that surrounds you flowed into your lungs when your lungs and rib cage expanded. Carbon dioxide flows out of your lungs when you exhale. Like liquids, gases flow and take up space. Therefore, gases and liquids can both be classified as fluids. Can solids be poured? Can solids be classified as a fluid? How does this video demonstrate gas? 4 Particles in Solids Solids are made up of particles that are tightly packed together. The particles cannot move around freely - they can only vibrate. Sugar, salt, and flour are examples of solids that can be poured, since they are ground into small pieces that can slip past each other. However, according to the particle model, each tiny fragment of these solids contain billions of even smaller particles that are tightly packed together. Solids form a pile when they are poured and they do not keep flowing apart from each other - they are not considered fluids. Particles in Liquids The particles that make up liquids have enough energy to pull away from each other. Particles in liquids slide around each other, while at the same time vibrating close together in small clusters. Liquid particles can slip past each other, as a result, the particles of a liquid can't hold their shape; instead, they fill a container and take the shape of that container. Liquid particles are so tightly packed together that they are easily affected by the downward pull of gravity. Liquids always flow to the lowest possible level. Liquids will also form a level surface when they are at rest. Liquids can be classified as fluids. 5 Particles in Gases Gas particles are so far apart from each other that there is an enormous amount of empty space between them. In fact, most gases seem invisible because there is so much empty space. The particle model can be used to explain why gas particles flow past each other easily, move in every direction (even against gravity), and move extremely far apart. Gas particles spread out so much that in a brief time, they fill up the space of an entire container or room. For this reason, gases, like liquids, take on the shape of the container in which they are sealed. Gases flow and can also be classified as a fluid. I can compare and contrast the three main states of matter, solid, liquid and gas. Self-reflection ❏ Goal: 6 Particle Model of Matter - PMOM I can identify the main points of the particle model of matter and explain them. Self-reflection ❏ Goal: 7 Air is a Fluid Video questions I can explain what fluid is and know which states of matter are considered a fluid. Self-reflection Goal: 8 Video questions 9 Change of State A change of state occurs when a substance is heated and the particles of the substance gain energy. If you were to cool the substance, the reverse changes of state would occur because the particles lose energy. 10 A change of state occurs when a substance is heated and the particles of the substance gain energy. If you were to cool the substance, the reverse changes of state would occur because the particles lose energy. Evaporation is a slower form of vaporization that occurs over a wide range of temperatures. A wet towel will dry even if the air temperature is cool. On a cool day it will simply take longer for the water to evaporate from a towel. 11 A change of state occurs when a substance is heated and the particles of the substance gain energy. If you were to cool the substance, the reverse changes of state would occur because the particles lose energy. 12 Change of State Diagram I can label a change of state triangle diagram and explain each term. Self-reflection Goal: 13 Video Questions 14  Topic 2 Mixing and Dissolving I can identify the 10 WHMIS symbols and explain why WHMIS is important. I can draw out a classification of matter chart with examples. I can identify four factors that affect the rate of dissolving. I can compare and contrast “Soluble & Insoluble” “Solute & Solvent” “Saturated, Unsaturated & Supersaturated” 15 Topic 2 Vocab Agitation Colloid Dissolving Emulsion Heterogeneous Homogeneous Insoluble Mechanical Mixture Mixture Phases Pure Substance Rate of Dissolving Saturated Soluble Solute Solution Solution Solvent Supersaturated Suspension Unsaturated Solution Classification of Matter Video Questions 16 17 I can draw out a classification of matter chart with examples. Self-reflection Goal: Pure Substances Elements such as iron, gold, oxygen, sulphur and carbon, are pure substances. Chemical compounds, such as water, table salt, and sugar are also pure substances. All pure substances can exist in the three states of matter. Video Questions 18 Mixtures Mixtures that look as though they have only one set of properties, such as paints, are called homogeneous. These mixtures are blended so thoroughly that every sample of the mixture will contain equal amounts of all matter that make it up. Homogeneous means that every part of the mixture is the same. A homogeneous mixture of substances in which no settling occurs is a solution. According to the particle model, solutions occur when the particles of the components slip in between each other in an even distribution. Mixtures that contain two or more materials that are still visible are called heterogeneous mixtures. Heterogeneous means made up of parts, or mixed. 19  Mixtures that are obviously heterogeneous are usually called mechanical mixtures. The separate parts of a mechanical mixture are called phases. For example, when oil separates from water, two distinct phases are visible. As well, the bubbles in soda water make up one phase, and the liquid portion makes up the other phase. Video Questions 20 In-Between Mixtures It can be difficult to determine correctly whether a mixture is homogeneous or heterogeneous without using a magnifying glass. Orange juice might appear to be a solution, but eventually the natural fruit sediment can settle. A heterogeneous mixture in which the particles settle slowly after mixing is a suspension. Suspended particles are large enough to be trapped by most fine filters. Homogenization helps fat globules in milk stay dispersed longer than suspended particles. A heterogeneous mixture in which the particles do not settle is a colloid. Colloidal particles are small enough to pass through most common filters. Fog is also an example of a colloid. The particles in a colloid can be dispersed for an even longer period by adding an emulsifying agent to form an emulsion. The emulsifying agent is often a protein that prevents the tiny droplets of fat from joining together. Dissolving The Particle Model of Matter can be used to explain the process of dissolving. A group of water particles can attract a sugar particle more strongly than the other sugar particles around it can. First the water particles pulls a sugar particle away from the other particles in the crystal. Then the motion of the water particles carries it away. This makes room for more water particles to move in and attract another sugar particle. 21 The Particle Model of Matter can be used to explain how a solute dissolves in a solvent. The solute is the substance that dissolves in a solvent to form a solution. The solvent is the substance that dissolves a solute to form a solution. There is usually more solvent than a solute in a solution. Another way to say "sugar dissolves in water" is to say "sugar is soluble in water". Soluble means able to be dissolved in a particular solvent. Both solutes and solvents may be solids, liquids, or gases. Goal: I can compare and contrast “Solute & Solvent” 22 The Universal Solvent Water has been called the "universal solvent" because it can dissolve so many materials. 23 Water is crucial for the survival of all living things. Approximately half of your blood is made up of water. The water portion of your blood dissolves and carries food molecules, vitamins, minerals, and other essential substances to all parts of your body. Blood carries dissolved wastes away from your body cells, too. Plants also need water to deliver nutrients and remove wastes. Water is easily polluted because it mixes readily with so many materials. When we measure how fast a solute dissolves in a solvent, we are measuring the rate of dissolving. Factors that affect the rate of dissolving include: Agitation (stirring), Size of solute, Temperature, Pressure I can identify four factors that affect the rate of dissolving. Goal: 24 The particles of one pure substance are not the same as those of another, so the degree of attraction is different for different substances. The limit to how concentrated a solution can become is called solubility. A saturated solution is one in which no more solute will dissolve in a specific amount of solvent at a given temperature. An unsaturated solution is one in which more of the solute would dissolve in a specific amount of solvent at the same temperature. A supersaturated solution is one in which more solute than would normally dissolve at a certain temperature has dissolved. You can prepare a supersaturated solution from some solutes by making a saturated solution, then cooling it without stirring. Goal: I can compare and contrast “Saturated, Unsaturated & Supersaturated” 25 Solubility Curves Simply mixing materials together does not always result in a solution. The pulp in orange juice is not soluble, and neither are the small droplets of fat in milk; these are insoluble. Insoluble means not able to be dissolved in a particular solvent. Why are some materials insoluble? - Use the Particle Model of Matter to explain. 26 Grass stains are caused by chlorophyll found in grass. The particles of chlorophyll are more attracted to each other than they are to water particles. To remove grass stains, you need to use a different solvent - one whose particles attract the particles of chlorophyll, like rubbing alcohol. Goal: I can compare and contrast “Soluble & Insoluble” 27 WHMIS Safety Symbols The Workplace Hazardous Materials Information System is used throughout Canada to identify dangerous materials found in all workplaces, including schools. For your own safety, make certain you understand what these symbols mean. When you see these symbols on containers in your classroom, at home, or in a workplace, use safety precautions. 28 29 I can identify the 10 WHMIS symbols and explain why WHMIS is important. Goal: 30  Topic 3 Separating Earth’s Mixtures I can describe different methods that mixtures are separated with. I can identify the solute and the solvent in a variety of mixtures. Topic 3 Vocab Desalination Fractional Distillation Distillation Dehydration Chromatography Filtration 31  Desalinating Water Desalination means removing the salt from salty water. What is the solute in the desert tent apparatus? Salt What is the solvent in the desert tent apparatus? Water What is being recovered in this example; the solvent or the solute? Solvent 32  Dehydration Dehydration is the process of removing water from a solution, through evaporation. Many convenience foods come in dehydrated form, such as pasta, sauces, milk, coffee, tea, soups, gravy, cake mixes, etc. To save time and reduce chances of spoilage while dehydration takes place, most food companies add heat to help speed up the evaporation process. What is the solute in the examples above? Tomato Particles What is the solvent in the examples above? Water What is being recovered in this example; the solvent or the solute? Solute 33  Distillation Distillation involves evaporating a solvent to separate it from the solute and then condensing it to a liquid. Water circulating in the condenser helps cool the steam as it passes through the tube. What is the solute in the example above? Salt What is the solvent in the example above? Water What is being recovered in this example; the solvent or the solute? Solvent 34  Fractional distillation Fractional distillation is used to process (separate) petroleum into petroleum products such as, gases, gasoline, jet fuel, kerosene, diesel and lubricating oils. Fractional distillation Videos 35 36  Topic 4 Flow Rate and Viscosity I can compare and contrast viscosity and flow rate. I can use the Particle Model of Matter to explain viscosity. I can explain how viscosity differs between liquids and gases. Topic 4 Vocab Viscosity Flow Rate 37 Viscosity:Viscosity is the measure of resistance to flow, how thick or thin a substance is. Flow rate: The rate that a fluid can flow, how fast the particles can move past each other. Videos 38 Viscosity The property that describes a liquid's thickness or thinness is called viscosity. Viscosity is the measure of resistance to flow. A thicker liquid is more viscous, and is more resistant to flow. Viscosity describes how easily a fluid flows. If you wanted to know how fast you could run, you might ask a friend to time how long it would take you to run, say, 100 m. The measurement would be your speed. In a similar way, you could measure how fast a fluid "runs". You could measure the time it takes for the fluid to flow from one point to another point. This measurement is called the fluid's flow rate. 39 Self-reflection ❏ Goal: I can compare and contrast viscosity and flow rate Viscosity and Product Performance Nail polish is applied as a slick fluid, but dries into a solid finish. Mascara is a very thick fluid, which dries extremely quickly after is is applied. The viscosity of both of these products is controlled by the amount of solvent that is added. 40 Any less, and they would both be too difficult to apply; any more, and they would take too long to dry and would possibly run off the intended areas. Solvents keep the ingredients dissolved and fluid while applying, then evaporate to leave a dry, solid finish. People in many occupations need to know how to adjust the viscosity of a substance to suit specific applications. For example: Chefs need to know how to make gravies thinner than sauces and frosting thicker than icings. Mechanics must choose an engine oil that is the right viscosity for the season. Artists need to know how to thin or thicken oil paints and acrylics. Technicians must control the viscosity of various chemicals in chemical processing plants. 41 Flowing Fluid Floods City 1. Use the particle model to explain why the tank burst. As the molasses heated up the particles started moving faster. They also spread out, this caused them to push against the walls of the tank. Eventually the tank walls gave way and the molasses escaped! 42 2. Energy is responsible for making things move. Use the PMOM to explain how something as viscous as molasses could move as quickly as it did on that particular day, at that particular moment. When you add heat to a substance you are adding energy. The more energy you add to particles the faster they move, increasing the flow flow rate and lowering the viscosity of the molasses. 3. For what purpose do you think the company used the molasses? Molasses is often used as a sweetener. Self-reflection ❏ Goal: I can use the Particle Model of Matter to explain viscosity. Viscosity of Liquids Another way to define viscosity is the resistance to flow. Resistance to flow creates internal friction. Friction is caused when two surfaces are rubbed together. Water particles slip past each other easily, but particles of honey have more internal friction and do not flow past each other as easily. The particle model of matter can be used to explain the internal friction of fluids. As particles of honey, for example, flow past other particles of 43 honey, they are attracted to each other so readily that they slow down as they pass by. Use the particle model of matter to explain how we might decrease the viscosity of honey. You could heat the honey up. Viscosity of Gases Gases flow differently than liquid particles. Gas particles are so far apart, and the attractive forces are so low, that the type of gas particle is less important than in a liquid. Particles of a gas are more likely to collide with each other than rub against each other. The internal friction of a gas is affected by temperature, and therefore, the temperature of a gas has a direct effect on viscosity. As gases are heated, the particles gain energy and move faster. The number of collisions between gas particles increases. Cooler gases contain particles that are not colliding as much or as often. The viscosity of a gas increases as it is heated, and decreases as it is cooled. Temperature has the opposite effect on the viscosity of gases as on liquids. 44 Video Self-reflection ❏ Goal: I can explain how viscosity differs between liquids and gases. 45  Topic 5 Density (Mass-to-Volume Ratio) I can explain density. I can use GRASP to solve density questions. I can explain how density varies between solids, liquids, and gases. Topic 5 Vocab Mass Weight Density Volume 46 Video Mass vs. Weight Mass and weight are not the same. Weight is the force of gravity exerted on an object. Gravity is the natural force that causes an object to move toward the centre of Earth. All forces, including weight, are measured in newtons (N). 47 Video Volume Volume can be measured in multiple ways, depending on the object. To measure the volume of regular shaped objects, you can use a ruler and a mathematical formula to calculate the object's volume eg: V = l x wxh To measure the volume of an irregular shaped object, you can use displacement. 48 To measure the volume of a fluid, you can use a graduated cylinder. Density Density can be described as the "crowdedness" of the particles that make up matter. In scientific terms, density is mass per unit volume of a substance. Video 49 Density: The ratio of mass to volume. Mass: Measurement of the amount of matter an object has. Volume: Measurement of the amount of space an object occupies. Video Self-reflection ❏ Goal: I can explain density Density of Solids, Liquids, and Gases We can use the particle model to help explain that different substances have different-sized particles. The size of the particles determines how many particles can "fit into" a given space. 50 Therefore, each substance has its own unique density, based on how close together the particles are. How is the density of a substance related to the substance's physical state? Both liquid water and water vapour have particles of the same size. The physical state of a substance affects its density. Video 51 When an object moves through a fluid, it pushes particles apart and moves between them. Particles in a solid cannot be pushed apart. In general, gases are less dense than liquids. For most pure substances, the density of the solid state is greater than the density of the liquid state. Water is an exception. Self-reflection ❏ Goal: I can explain how density varies between solids, liquids and gases Density Calculations As long as the temperature and pressure stay the same, the mass-to-volume ratio, or density, of any pure substance is a constant, which means it does not change. Example 1: What shiny solid has a mass of 356 g and a volume of 40 cm3? 52 D=M D=356 D=8.9 V 40 According to the chart on the page about Nickel has a density of 8.9 g/cm3 Therefore the shiny solid is Nickel. Example 2: Ms. Scott smelted 5.40 grams of aluminum pop cans. What volume of aluminum did she smelt? The density of Aluminum is 2.7g/cm3 according to the chart above. D=M 2.7=5.4 another way to say this is 2.7=5.4 We made an V v 1= V equivalent Fraction Now we can cross multiply and divide. 5.4 x 1= 5.4 divided by 2.7= 2. The volume of Aluminum that she smelt is 2 cm3. Example 3: An unidentified substance has a volume of 5.0 cm3 and is known to have a density of 8.92 g/cm3. What is the substance? What is the mass of the object? D= M 8.92=M Let’s make an equivalent fraction V 5 8.92= M Now we can cross multiply and divide 53  1 5 8.92 x 5= 44.6 divide by 1 = 44.6 The mass is 44.6 g. Self-reflection ❏ Goal: I can use GRASP to solve density problems 54  Topic 6 Buoyancy or “Anti-Gravity” Force I can explain buoyancy and relate it to why an object will sink or float. I can explain average density. I can explain Archimedes' Principle. I can explain what a hydrometer is. Topic 6 Vocab 55 Buoyancy Average Density Archimedes’ Principle Displacement Hydrometer Neutral Buoyancy Buoyant Force Gravity Buoyancy Video Buoyancy refers to the ability of a fluid to support an object floating in or on the fluid. Buoyancy is the tendency for materials to rise or float in a fluid. Without it, matter could not be transported from one 56 place to another. It is also referred to as the buoyant force, it is the upward force exerted on objects submerged in fluids. The transportation of nutrients through our bloodstream, pollen floating in the air, and boats and planes moving around the world would not be possible without it. Buoyancy is an upward force (push) that is working in the opposite direction of gravity (pull). Since it is a force, it is measured in newtons (N). Self-reflection ❏ Goal: I can explain buoyancy and relate it to why an object will sink or float Cartesian Diver Demo Using your knowledge of density and buoyancy, explain how a cartesian diver works. 57 Average Density Ships can be built of steel (density = 9.0 g/cm3) as long as they have large, hollow hulls. A large, hollow hull ensures that the average density of the ship is less than that of water. Video Average density is useful because it enables objects that would otherwise sink - such as large ships and oil rigs - to float. Average density also helps floating objects to sink. 58  Most fish have an organ called a swim bladder. The swim bladder, a large sac near the spine of the fish, contains a mixture of air and water. The fish's depth in the water depends on how much air is inside the sac. As the amount of air decreases, the fish sinks lower. As the amount of air increases, the fish rises closer to the surface. This depth-control structure has been adapted in the submarine, allowing it to adjust its depth underwater. The buoyant force of air is much smaller than the buoyant force of water. Although air particles are extremely far apart, they are still close enough together to support some objects. 59 How is the average density of a boat affected by Zebra mussels? The zebra mussels increase the average density of the boat. Self-reflection ❏ Goal: I can explain average density 60 Archimedes’ Principle Video Archimedes' principle: The buoyant force acting on an object equals the weight (force of gravity) of the fluid displaced by the object. Archimedes' principle is useful in predicting whether objects will sink or float. The buoyant force does not depend on the weight of the submerged object, but rather on the weight of the displaced fluid. A solid cube of aluminum, a solid cube of iron, and a hollow cube or iron, all of the same volume would experience the same buoyant force! Video 61  Will this object sink or float? What is the buoyant force acting on this object? Video Self-reflection ❏ Goal: I can explain Archimedes’ Principle 62 Hydrometer The relationship between buoyancy and density is the basis for the hydrometer, an instrument designed to measure liquid density. Hydrometers are widely used in the food and beverage industries. Although they measure density, these instruments can be used to determine other values indirectly. For example, they can be used to determine the sugar content of liquids or the alcohol content of wine. Video Self-reflection ❏ Goal: I can explain what a hydrometer is 63 Measuring Buoyancy All liquids do not have the same density. Investigate whether various liquids exert the same buoyant force. Use the photographs below to calculate the buoyant force for each liquid. 64  Topic 7 Fluid Pressure I can explain and calculate pressure. I can explain why gas can be compressed. I can explain the advantages of compression Topic 7 Vocab Pressure Compressible Incompressible 65 Pressure Pressure is a measure of the force acting perpendicular to a unit area. When you press your hand against a wall, you are applying pressure on that particular area of the wall. If the force is increased, the pressure will increase. What happens if the area is increased? Pressure can be calculated by using the following formula: Force is measured in newtons (N), and area is often measured in square metres (m2). The unit for pressure, therefore, is newtons per square meter (N/m2). This unit is also called a pascal (Pa), named after the French scientist Blaise Pascal (1623-1662). 66 Let's try a problem together. Remember to follow GRASP! A force of 638 N was applied over an area of 43 m2. What was the pressure? P=F/A P= 638 N 43 m2 P= 14.83 pa The pressure is 14.83 Pascals. Self-reflection ❏ Goal: I can explain and calculate pressure 67 Compressed Gas How is the compression of a gas made possible? 1. The gas must be enclosed in a sealed container with sturdy walls. Gas molecules distribute themselves equally throughout their containers. 2. There is so much space between the particles that, even after the particles are squeezed closer together, they are still far enough apart to behave as a gas. 3. An external, or outside, force is applied to the enclosed gas, to push the particles closer together. Self-reflection ❏ Goal: I can explain why gas can be compressed. 68 Compressed Liquids and Solids Because solids and liquids cannot be squeezed into a smaller volume, they are said to be incompressible. What happens to liquids and solids when an external force is applied? Instead of changing volume of either the solid or the liquid, the applied force is transmitted (passed along), from one particle to the next, throughout the substance, somewhat like falling dominoes. Advantages of Compression A useful property of gases is their ability to exert a force back (counterforce) when they are compressed. This property can be used to cushion shocks. For example, the air in a car tire pushes back against the force exerted by the weight of the car. Otherwise, the car would simply sink to the ground. If the car hits a bump, the extra force compresses the air in the tires even further. This allows the effect of the force to be spread out over the entire tire, rather than being transmitted directly to the body of the car and its passengers. When the extra force is removed, the air returns to its original volume, and the tire resumes its original shape. 69 Self-reflection ❏ Goal: I can explain advantages of compression Atmospheric Pressure Video 70 Earth's atmosphere is approximately 160 km thick. Gravity keeps the envelope of air around Earth. Why don't you feel weighed down by air? The pressure of Earth's atmosphere is so well balanced by your body, both inside and out, that you hardly notice air pressure. What structure do we have that helps us to maintain constant pressure? Video If the inside of a closed container experiences a lower air pressure than the air pressure pushing on the outside, the walls of the container will buckle and cave in. In other words, the lower air pressure inside the container doesn't balance the higher air pressure outside the container. This results in unbalanced forces. 71 Video Did you know? 72  Topic 8 Fluid Systems I can explain a hydraulic system. I can explain a pneumatic system. Topic 8 Vocab Hydraulic System Pneumatic System Fluid Systems 73 Particles always flow from areas of high pressure to low pressure. When high energy gas particles are squeezed inside strong-walled containers, they exit through holes or cracks with great force. If a liquid is also present, the gas will push a fine foam or spray of the liquid particles as it exits. Although aerosols no longer contain the chlorofluorohydrocarbons (CFCs), which damage the ozone layer, there are still dangers associated with aerosols. The liquid/gas mixture inside is under so much pressure that high temperatures could cause the energy of the particles inside to become stronger than the container, and cause the container to rupture - causing an explosion. Hydraulic Systems Hydraulics is the study of pressure in liquids. Devices that transmit applied forces through a liquid to move something else, because of pressure, are called hydraulic systems. Hydraulic systems can be used to transport fluids over large distances. Today, water, natural gas, and oil are typical examples of fluids transported in extensive pipelines. Pumps provide the force that pushes fluid through the pipes. These traveling fluids need to be placed under pressure for them to travel and move against gravity. There must be enough pressure in the pipes to transport the liquid over a large distance, but not enough to burst the pipes. 74 Self-reflection ❏ Goal: I can explain a hydraulic system. Pneumatic Systems Pneumatic systems are similar to hydraulic systems, except gases are used instead of liquids. The operation of most pneumatic systems is based on the fact that gases can be compressed. Therefore, compressors - devices that compress air - are needed. Air pressure builds up in these devices. As the pressure is released, the compressed air decompresses. In other words, the particles start to move apart suddenly, creating a strong, steady force that can perform powerful tasks. In pneumatic systems, an enclosed gas can transmit a force, causing motion. 75 Self-reflection ❏ Goal: I can explain a pneumatic system. Hydraulic and Pneumatic Systems Videos 76