FOUNDATIONS OF CHEMISTRY CHAPTER 7.2 PHYSICAL PROPERTIES Marshall-Arts

Questions: What are some physical properties of matter? How are physical properties used to separate mixtures?

Big Ideas Types of Properties Separating Mixtures Some properties of matter are size- dependent, meaning that they depend on the amount of matter present. Mass and volume are examples of size- dependent properties. Other properties are size-independent, which means that they do not depend on the amount of matter present. Melting point, boiling point, density, conductivity, and solubility are size-independent properties. Using the unique set of physical properties of each substance, it is possible to separate substances in a mixture. For example, petroleum is a mixture of hydrocarbons and other compounds. Through fractional distillation, petroleum is heated, and each component boils off as the unique boiling point of the component is reached.

How is gold different from water? What is another method this miner might use to separate gold from river water? How can you use some of your vocabulary words to describe some of the matter in this photograph?

Physical Properties The arrangement of atoms determines whether matter is a substance or a mixture. The arrangement of atoms also determines the properties of different types of matter. Each element and compound has a unique set of properties. Properties can be observed or measured. Physical property - a characteristic of matter that you can observe or measure without changing the identity of the matter.

What are the physical properties of this item What are the physical properties of this item? (think about state, length, volume, mass, density, color, velocity, & shininess)

States of Matter (can you list them?)

Size Dependent Properties - Physical properties depend on the size or amount of matter. Size Independent Properties - Physical properties do not depend on the size or amount of matter. (These properties are the same for both small and large samples.)

Boiling/Melting Point Conductivity Solubility Draw this table in your notebooks. We will be filling it out during the lesson. PROPERTY States of Matter Boiling/Melting Point Conductivity Solubility Description Whether something is a solid, a liquid, or a gas Size Dependent or Size Independent Size independent How the property is used to separate a mixture (example) A liquid can be poured off of a solid

Did you know? Particles or atoms and groups of atoms, that make up all matter are constantly moving and are attracted to each other? States of Matter Interaction https://phet.colorado.edu/sims/html/states-of-matter/latest/states-of-matter_en.html

Size-Independent Properties Some physical properties do not depend on amount of matter present. (ex. Melting point, boiling point, density, conductivity, and solubility.) melting/boiling point The temperature at which a substance changes from a solid to a liquid is its melting point. The temperature at which a substance changes from a liquid to a gas is its boiling point.

Size-independent Properties Some physical properties do not depend on amount of matter present. (ex. Melting point, boiling point, density, conductivity, and solubility.) Conductivity Electrical conductivity is the ability of matter to conduct (or carry along), an electric current. Thermal conductivity is the ability of a material to conduct thermal energy.

Size-independent Properties Some physical properties do not depend on amount of matter present. (ex. Melting point, boiling point, density, conductivity, and solubility.) Solubility The ability of something to dissolve in another. Powdered drink mix is soluble in water, sand is not.

Solutions Solution - a homogeneous mixture of particles so small that they cannot even be seen with a microscope and will never settle to the bottom of their container. Examples: vinegar, soda (unopened), and hydrogen peroxide

Types of mixtures Colloid Suspension Mixture mart activity Colloid Suspension Type of mixture with particles that are larger than those in solution but still too light to settle out. Ex. milk (water & fat), fog (water & air), cool whip Detecting is sometimes difficult so shining a beam of light at colloid will make the light scatter - this scattering of light is called the Tyndall effect. Heterogeneous mixture containing a liquid in which visible particles settle. Ex. italian dressing, muddy pond water, chocolate milk (the chocolate and milk) If it needs shaking to mix, then it is a suspension.

Mixture Mart Activity HW: handout

How the property is used to separate a mixture (example) Draw this table in your notebooks. We will be filling it out during the lesson. This is the 2nd table for this lesson. PROPERTY Magnetism Mass Volume Density Description Size Dependent or Size Independent How the property is used to separate a mixture (example)

Size-dependent Properties Some physical properties, such as mass, weight and volume, depend on the size or amount of matter. Mass The amount of matter in an object. Mass is sometimes confused with weight. What is the difference?

Size-dependent Properties Some physical properties, such as mass, weight and volume, depend on the size or amount of matter. Volume The amount of space that something takes up. Which state of matter takes on the shape of its container? Which state of matter fills its container?

I Size-Independent Properties density Some physical properties do not depend on amount of matter present. (ex. Melting point, boiling point, density, conductivity, and solubility.) density The mass per unit volume of a substance. I density

Separating Mixtures Remember that substances that make up mixtures are not held together by chemical bonds. When they form a mixture, the properties of the individual substances do not change. They can usually be separated. Ways to separate: There are six ways to separate mixtures including sedimentation, decantation, filtration, evaporation, crystallization and distillation.

Homework pg. 246

For use with crime scene LAB activity