Chemistry The Study of Matter Alchemists hard at

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Chemistry – The Study of Matter Alchemists hard at work.

Chemistry – The Study of Matter Alchemists hard at work.

Chemistry n n The study of the composition, structure, and properties of matter and

Chemistry n n The study of the composition, structure, and properties of matter and the changes it undergoes. Branches: n n n Organic Inorganic Physical Analytical Biochemistry Theoretical

Research – What are some ‘modern technologies’ that have impacted the way we live?

Research – What are some ‘modern technologies’ that have impacted the way we live? n Basic Reasearch n n Applied Research n n Increasing knowledge Solve a specific problem Technological Development n Production and use of products to improve quality of life

Matter n 4 states of matter n n n Solids Liquids Gases Plasma Kinetic

Matter n 4 states of matter n n n Solids Liquids Gases Plasma Kinetic Molecular Theory (KMT) n All matter is made of particles that are in constant motion

Solids n n n Very low KE – particles vibrate Fixed shape Fixed volume

Solids n n n Very low KE – particles vibrate Fixed shape Fixed volume

Liquids n n n Low KE – particles can move around but are close

Liquids n n n Low KE – particles can move around but are close together Variable shape Fixed volume

Gases n n n High KE – particles separate and move freely Variable shape

Gases n n n High KE – particles separate and move freely Variable shape Variable volume

Plasma n Very high KE n n n particles collide with enough energy to

Plasma n Very high KE n n n particles collide with enough energy to break into charged particles Gas-like – variable shape and volume Ex: stars, fluorescent light bulbs

The Four States of Matter Solid, Liquid, Gas, and Plasma

The Four States of Matter Solid, Liquid, Gas, and Plasma

Phases of Matter

Phases of Matter

Intensive v. Extensive Properties n Intensive property does NOT depend on sample size. n

Intensive v. Extensive Properties n Intensive property does NOT depend on sample size. n n Ex: density, melting point Extensive property does depend on sample size. n Ex: mass, volume, energy

Physical Properties and Changes n n Can be observed without changing the identity of

Physical Properties and Changes n n Can be observed without changing the identity of the substance Examples: n n n Color Viscosity Melting and boiling points Thermal conductivity Electrical conductivity n More Examples: n n n n n Specific heat Luster State of matter Phase changes Magnetism Solubility Malleability Ductility Crystal Form Tenacity

Chemical Properties and Changes n n n Ability to change into a new substance

Chemical Properties and Changes n n n Ability to change into a new substance Reactants become products Examples: n n n n Flammable Rusting Reactivity Oxidation Acidity/basisity Corrosion Inert

Chemical and Physical Properties

Chemical and Physical Properties

All chemical and physical changes involve ENERGY!!!

All chemical and physical changes involve ENERGY!!!

Signs of a Chemical Change �change in color or odor �formation of a gas

Signs of a Chemical Change �change in color or odor �formation of a gas �formation of a precipitate (solid) �production of light �absorption or release of heat

Name that property n n n Honey and motor oil are very slow to

Name that property n n n Honey and motor oil are very slow to pour. What property bests describes this property? ? ? Viscosity What property of liquids would you look for to start charcoal for a BBQ? ? Flammability Iron heats up faster than aluminum. What property is this? ? Specific Heat

Name that property (more) n n n Paints made of silver are applied to

Name that property (more) n n n Paints made of silver are applied to the back of mirrors. What property of silver is useful? ? Luster The copper on the Statue of Liberty has turned green. What property is causing this? ? ? Corrosion or Oxidation Jewelry can be pounded to form artistic designs. What property is this? ? Malleability

Name that property (still) n n n A good frying pan heats food evenly.

Name that property (still) n n n A good frying pan heats food evenly. What property of frying is this? ? Thermal Conductivity Quartz forms hexagons and diamonds form cubes. What property is this? ? ? Crystal Form You purchase a clear stone that might be a diamond. What simple test can you make to determine if it is actually a diamond? ? ? Hardness

Name that property (lastly) n n You accidentally drop an iron bolt into a

Name that property (lastly) n n You accidentally drop an iron bolt into a hard-to-reach place in your automobile engine. What property of iron enables you to retrieve the bolt without having to find someone with small hands? Magnetism

B. Physical vs. Chemical n Examples: n rusting iron chemical n dissolving in water

B. Physical vs. Chemical n Examples: n rusting iron chemical n dissolving in water physical n burning a log chemical n melting ice physical n grinding spices physical

Solid Melting Deposition Freezing Sublimation Liquid Condensation Evaporation Gas

Solid Melting Deposition Freezing Sublimation Liquid Condensation Evaporation Gas

Energy & Phase Changes n n Heat of vaporization - Amount of heat needed

Energy & Phase Changes n n Heat of vaporization - Amount of heat needed to change a liquid into a gas at its boiling point Heat of fusion - Amount of heat required to melt a solid at its melting point

Phase Change Diagram n n n Show the changes of state for any subs.

Phase Change Diagram n n n Show the changes of state for any subs. Show the temperatures where the phase change occurs Is more energy used to convert ice to water or water to steam?

n Insert phase diagram on p. 49

n Insert phase diagram on p. 49

Classification Flowchart MATTER yes MIXTURE yes Is the composition uniform? Homogeneous Mixture (solution) PURE

Classification Flowchart MATTER yes MIXTURE yes Is the composition uniform? Homogeneous Mixture (solution) PURE SUBSTANCE no Heterogeneous Mixture Colloids no Can it be physically separated? yes Can it be chemically decomposed? Compound Suspensions no Element

Classification of Matter n Examples: n n n Graphite Pepper Sugar (sucrose) Paint Soda

Classification of Matter n Examples: n n n Graphite Pepper Sugar (sucrose) Paint Soda Element Heterogeneous mixture Compound Heterogeneous mixture Solution (homogeneous mixture

Pure Substances Element 1. n n Composed of identical atoms Ex: Copper wire, aluminum

Pure Substances Element 1. n n Composed of identical atoms Ex: Copper wire, aluminum foil

Pure Substances 2. H Compounds Composed of two or more elements in a fixed

Pure Substances 2. H Compounds Composed of two or more elements in a fixed ratio H C C H OH O H C OH Properties differ from individual elements Ex: glucose, caffeine C H OH

Mixtures n Combination of 2 or more pure substances 1. Homogeneous mixtures 2. Colloids

Mixtures n Combination of 2 or more pure substances 1. Homogeneous mixtures 2. Colloids Heterogeneous mixtures 3. Suspensions

Mixtures Homogeneous 1. n n AKA: Solution Very small particles that do not settle

Mixtures Homogeneous 1. n n AKA: Solution Very small particles that do not settle No Tyndall effect Ex: rubbing alcohol, salt water

Liquid Mixtures n Miscible – liquids are able to dissolve into each other n

Liquid Mixtures n Miscible – liquids are able to dissolve into each other n n n Homogeneous mixture of liquids Gasoline = homo. mixture of 100 compounds Immiscible – liquids are NOT able to dissolve into one another n n Heterogeneous mixture of liquids Oil and water will not mix

Mixtures Colloid 2. n n Heterogeneous Medium sized particles that do NOT settle Tyndall

Mixtures Colloid 2. n n Heterogeneous Medium sized particles that do NOT settle Tyndall effect Ex: milk

colloid solution Which glass contains a colloid? Colloids scatter light, making a beam visible.

colloid solution Which glass contains a colloid? Colloids scatter light, making a beam visible.

Examples of Colloids Dispersing Medium Dispersed Substance Colloid Type Fog, aerosol sprays Gas Liquid

Examples of Colloids Dispersing Medium Dispersed Substance Colloid Type Fog, aerosol sprays Gas Liquid Aerosol Smoke, airborne bacteria Gas Solid Aerosol Whipped cream, soap suds Liquid Gas Foam Milk, mayonnaise Liquid Emulsion Paint, clays, gelatin Liquid Sol Marshmallow, Styrofoam Solid Gas Solid foam Butter, cheese Solid Liquid Solid emulsion

Mixtures Suspension 3. n n Heterogeneous Large particles that will settle Tyndall effect Ex:

Mixtures Suspension 3. n n Heterogeneous Large particles that will settle Tyndall effect Ex: fresh squeezed lemonade

Mixtures – Colloid, suspension, or solution? ? n Examples n Mayonnaise n Muddy water

Mixtures – Colloid, suspension, or solution? ? n Examples n Mayonnaise n Muddy water n Fog n Salt water n Italian salad dressing Colloid Suspension Colloid Solution Suspension

The Periodic Table n n n Rows – Periods Columns – Groups or Families

The Periodic Table n n n Rows – Periods Columns – Groups or Families Three main types of elements 1. 2. 3. Metals Nonmetals Metalloids

Metals n n n Conducts heat and electricity Malleable Ductile

Metals n n n Conducts heat and electricity Malleable Ductile

Nonmetals n n Many are gases at room temperature Solids are brittle

Nonmetals n n Many are gases at room temperature Solids are brittle

Metalloids n n n Touch the stair-step line (except Al) Some characteristics of metals

Metalloids n n n Touch the stair-step line (except Al) Some characteristics of metals and nonmetals Semiconductors