Types of Mixtures PDF
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This document provides an overview of different types of mixtures, including homogenous and heterogenous mixtures, solutions, colloids, and suspensions. It also discusses emulsions and emulsifiers. The document includes helpful examples and diagrams.
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Types of mixture Learning objectives: Understand the difference between homogenous and heterogenous mixtures Understand the difference between a solution, colloid and suspension Understand what an emulsion is Be able to give examples of all of the above Mixtures Pure substances incl...
Types of mixture Learning objectives: Understand the difference between homogenous and heterogenous mixtures Understand the difference between a solution, colloid and suspension Understand what an emulsion is Be able to give examples of all of the above Mixtures Pure substances include compounds and elements. An important feature of pure substances is that they are very difficult to break down into their individual parts. For example, if you were given a piece of pure salt (or sodium chloride), it would be very difficult to split it into sodium and chlorine. Mixtures, on the other hand, are much easier to separate. Mixtures Mixtures can be classed as homogenous mixtures or heterogenous mixtures: Homogenous mixtures are those in which particles are spread out evenly throughout the mixture. Heterogenous mixtures are those in which the different components are scattered unevenly throughout the mixture. Sodium chloride Chocolate milkshake Sand and water Mixtures- notes Pure substances include compounds and elements. Pure substances are very difficult to break down into their individual parts. Mixtures are much easier to separate. ______genous mixtures are those in which particles are spread out evenly throughout the mixture. Examples are (choose from pink words below) ______genous mixtures are those in which the different components are scattered unevenly throughout the mixture. Examples are (choose from pink words below) Nitrogen and oxygen in air, salad, steel, vinegar, chocolate chip cookies, brass, black coffee, natural gas, soda with ice Draw a diagram using two different coloured particles to show the difference between the distribution of particles in a homogenous and a heterogenous mixture Mixtures- answers Pure substances include compounds and elements. pure substances are very difficult to break down into their individual parts. Mixtures are much easier to separate. Homogenous mixtures are those in which particles are spread out evenly throughout the mixture. Examples are Nitrogen and oxygen in air, steel, vinegar, brass, black coffee, natural gas Heterogenous mixtures are those in which the different components are scattered unevenly throughout the mixture. Examples are salad, chocolate chip cookies, soda with ice Types of Mixture Another way to categorise mixtures is based on particle size. This gives us three types of mixture: Solutions — containing particles that completely dissolve Colloids — contain small particles Suspensions — contain larger particles Saltwater = solution Milk = colloid Mud stirred into water = suspension Colloids A mixture that contains suspended particles too small to settle or be removed by filtering is called a colloid. Unlike solutions, which are clear, colloids are cloudy. Colloids can be formed by solids, liquids or gases. Examples of colloids include mist, cappuccino froth, whipped cream, ice-cream and paint. Emulsions An emulsion is a specific type of colloid involving two or more insoluble liquids. In emulsions, one liquid is able to spread evenly through another liquid, rather than settling into layers as it usually would. Unhomogenised milk, is not an emulsion due to the layer of cream floating on the milk. Homogenised milk and mayonnaise are examples of emulsions, as is the liquid spread through water. Raw Milk Water and oil are immiscible- this means that they do not mix. Oil forms a layer on top of water. We can shake the mixture of oil and water and form an emulsion, with the oil dispersed throughout the water. However, if we left this emulsion, in about 5-10 minutes the two layers would re-form. Emulsifiers are chemicals which are added to mixtures of immiscible liquids to keep the two liquids dispersed as an emulsion. lecithin in egg yolk, is the emulsifier used in mayonnaise to help keep the fats in the oils, mixed in with the lemon juice or vinegar Colloids are classified as foams, aerosols, emulsions, gels, or sols, depending on the nature of the dispersed phase and dispersion medium. Familiar examples of colloids include mayonnaise, milk, fog, smoke, and gelatin. Extra info on colloids- not tested A gel is a colloid of solid particles in a liquid medium. A sol consists of liquid particles in a solid medium. An emulsion is a colloid formed by two or more liquids. A foam forms by gas particles trapped within a liquid or solid. An aerosol is a colloid consisting of liquid or solid particles dispersed in a gas. Liquid Dispersed Solid Dispersed Dispersion Medium Gas Dispersed Phase Phase Phase liquid aerosol solid aerosol Gas none known (mist, fog, hair spray) (smoke, ice cloud) foam emulsion sol Liquid (shaving cream, (milk, mayonnaise, (ink, paint) whipped cream) hand lotion) solid foam gel solid sol Solid (pumice, styrofoam, (gelatin, agar, jelly, (coloured gems) marshmallow) butter) The Tyndall Effect is the phenomenon of the scattering of light by the particles present in a colloid or suspension. The only difference between a colloid and a suspension is the size of the particles. To be classified as a colloidal solution, a material must have particles with dimensions in the range of 1-1000 nanometers. In a suspension the size of the particles can range from 10 to 1000 micrometers. Colloids and suspensions appear cloudy whereas solutions appear clear https://www.youtube.com/watch?v=bC_czAL24zY What are Emulsions? | Properties of Matter | Chemistry | FuseSchool 3 min Colloids- notes There are three main types of mixtures: ____________ — containing very small particles (1000nm) ___________ are clear but __________ and __________________ are cloudy. A light beam will be visible when shone through a _________ and a ___________ but will not be visible when shone through a _________________ A colloid is a mixture that contains suspended particles too small to settle or be removed by filtering. Examples of colloids include milk, mist, cappuccino froth, whipped cream, gelatin, ice-cream and paint, Styrofoam, ink. Colloids can be formed by solids, liquids or gases. Colloids are classified as foams, aerosols, emulsions, gels, or sols, depending on the nature of the dispersed phase and dispersion medium. An emulsion is a specific type of colloid involving two or more insoluble _________. In ____________, one liquid is able to spread evenly through another liquid, rather than settling into layers as it usually would. Unhomogenised milk, is not an emulsion due to the layer of cream floating on the milk. Homogenised milk and mayonnaise, moisturiser and salad dressing are examples of colloids. Water and oil are _______________ this means that they do not mix. Oil forms a layer on top of water. ________________ are chemicals which are added to mixtures of immiscible liquids to keep the two liquids dispersed as an emulsion. Help words below can be used more than once Suspensions, immiscible, emulsions, colloids, emulsifiers, liquids, solutions Colloids- notes There are three main types of mixtures: Solutions — containing very small particles (1000nm) Solutions are clear but colloids and suspensions are cloudy. A light beam will be visible when shone through a colloid and a suspension but will not be visible when shone through a solution A colloid is a mixture that contains suspended particles too small to settle or be removed by filtering. Examples of colloids include milk, mist, cappuccino froth, whipped cream, ice-cream and paint. Colloids can be formed by solids, liquids or gases. Colloids are classified as foams, aerosols, emulsions, gels, or sols, depending on the nature of the dispersed phase and dispersion medium. An emulsion is a specific type of colloid involving two or more insoluble liquids. In emulsions, one liquid is able to spread evenly through another liquid, rather than settling into layers as it usually would. Unhomogenised milk, is not an emulsion due to the layer of cream floating on the milk. Homogenised milk and mayonnaise, moisturiser and salad dressing are examples of colloids. Water and oil are immiscible- this means that they do not mix. Oil forms a layer on top of water. Emulsifiers are chemicals which are added to mixtures of immiscible liquids to keep the two liquids dispersed as an emulsion. https://ed.ted.com/lessons/the-science-of- macaroni-salad-what-s-in-a-mixture-josh-kurz Which type of food in the macaroni salad is a suspension? Which type of food in the macaroni salad is a solution? Which type of food in the macaroni salad is a colloid? Answers Which type of food in the macaroni salad is a suspension? (mustard) Which type of food in the macaroni salad is a solution? (vinegar) Which type of food in the macaroni salad is a colloid? (mayo) End of lesson checkpoints 1. Which has an even distribution of particles, a homogenous or a heterogenous mixture? 2. Which has the biggest particles in: a solution, colloid or suspension? 3. Which has the smallest particles in: a solution, colloid or suspension? 4. Is an emulsion a solution, colloid or suspension? 5. What is does immiscible mean? 6. Which mixture is clear, meaning that light would shine through: a solution, colloid or suspension? 7. Muddy water would be classified as which of the following: a solution, colloid or suspension? 8. Saltwater would be classified as which of the following: a solution, colloid or suspension?