Chemistry – The Study of Matter Alchemists hard at work.

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

Research Basic Reasearch Increasing knowledge Applied Research Solve a specific problem Technological Development Production and use of products to improve quality of life

Matter 4 states of matter Solids Liquids Gases Plasma Kinetic Molecular Theory (KMT) Particles are in constant motion The kinetic energy of the particles increases as temperature increases

Solids Very low KE – particles vibrate Fixed shape Fixed volume

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

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

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

Phases of Matter

Matter Flowchart Homogeneous Mixture (solution) Is the composition uniform? noyes MATTER Can it be physically separated? Heterogeneous MixtureCompoundElement MIXTUREPURE SUBSTANCE yesno Can it be chemically decomposed? noyes ColloidsSuspensions

Classification of Matter Examples: Graphiteelement Pepperheterogeneous mixture Sugar (sucrose)compound Paintheterogeneous mixture Sodasolution (homogeneous mixture)

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

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

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

Colloids scatter light, making a beam visible. Solutions do not scatter light. solution colloid Which glass contains a colloid?

Mixtures 1. Solution Homogeneous Very small particles No Tyndall effect Particles don’t settle Ex: rubbing alcohol

Mixtures 2. Colloid Heterogeneous Medium sized particles Tyndall effect Particles don’t settle Ex: milk

ExamplesDispersing Medium Dispersed Substance Colloid Type Fog, aerosol spraysGasLiquidAerosol Smoke, airborne bacteriaGasSolidAerosol Whipped cream, soap sudsLiquidGasFoam Milk, mayonnaiseLiquid Emulsion Paint, clays, gelatinLiquidSolidSol Marshmallow, StyrofoamSolidGasSolid foam Butter, cheeseSolidLiquidSolid emulsion

Mixtures 3. Suspension Heterogeneous Large particles Tyndall effect Particles settle Ex: fresh squeezed lemonade

Mixtures – Colloid, suspension, or solution?? Examples Mayonnaisecolloid Muddy watersuspension Fogcolloid Salt watersolution Italian salad dressingsuspension

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

Metals Conducts heat and electricity Malleable Ductile

Nonmetals Many are gases at room temperature Solids are brittle

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