MATTER Classification of Matter I Composition of Matter

MATTER Classification of Matter I. Composition of Matter w Matter Flowchart w Pure Substances w Mixtures

A. Matter Flowchart MATTER yes MIXTURE yes Is the composition uniform? Homogeneous Mixture (solution) no Can it be separated by physical means? PURE SUBSTANCE no Heterogeneous Mixture yes Can it be decomposed by chemical means? Compound no Element

B. Pure Substances ö Element w matter composed of identical atoms w EX: copper

Periodic Table of Elements

B. Pure Substances ö Compound/ Molecule w matter composed of 2 or more elements in a fixed ratio w properties differ from those of individual elements w chemically combined w EX: salt (Na. Cl) or water (H 2 O)

Chemical Formulas ö Shows how many atoms of each element are in the substance. Example: C 16 H 10 N 2 O 2 is a blue dye. ö The number of atoms of each element is written after the element’s symbol as a subscript. ö If only one atom is present, no subscript is needed.

Chemical Formulas ö You try. C 12 H 22 O 11 How many atoms of each element are in this formula? C is for carbon. H is for hydrogen. O is for oxygen.

C. Mixtures ö Variable combination of 2 or more pure substances. ö Homogeneous Mixture (Solution) w even distribution of components w very small particles w particles never settle w EX: saline solution

C. Mixtures ö Heterogeneous Mixture w uneven distribution of components w Can physically separate w Colloids and Suspensions w EX: granite

C. Mixtures ö Colloid w medium-sized particles w Tyndall effect - particles scatter light (looks cloudy) w particles never settle w EX: milk

C. Mixtures ö Suspension w large particles w particles scatter light w particles will settle (needs to be shaken) w EX: fresh-squeezed lemonade

Law of Conservation of Mass and Energy ö Mass cannot be created nor destroyed ö Energy cannot be created nor destroyed; it can be transformed or transferred to other forms of energy.

w. MATTER Solids, Liquids, & Gases I. States of Matter w Kinetic Molecular Theory w Four States of Matter w Thermal Expansion

A. Kinetic Molecular Theory ö KMT w Tiny, constantly moving particles make up all matter. w The kinetic energy (motion) of these particles increases as temperature increases.

B. Four States of Matter ö Solids w low KE - particles vibrate but can’t move around w definite shape & volume w crystalline - repeating geometric pattern w amorphous - no pattern (e. g. glass, wax)

B. Four States of Matter ö Liquids w higher KE - particles can move around but are still close together w indefinite shape w definite volume

B. Four States of Matter ö Gases w high KE - particles can separate and move throughout container w indefinite shape & volume

B. Four States of Matter ö Plasma w very high KE - particles collide with enough energy to break into charged particles (+/-) w gas-like, indefinite shape & volume w stars, fluorescent light bulbs, TV tubes

C. Thermal Expansion ö Most matter expands when heated & contracts when cooled. ö Temp causes KE. Particles collide with more force & spread out. ö EX: thermostats (bimetallic strip)

w. MATTER Solids, Liquids, & Gases II. Changes in State w Phase Changes w Heating Curves

A. Phase Changes ö Melting w solid to liquid ö Freezing w liquid to solid melting point = freezing point

A. Phase Changes ö Vaporization (boiling) w liquid to gas at the boiling point ö Evaporation w liquid to gas below the boiling point ö Condensation w gas to liquid

A. Phase Changes ö Sublimation w solid to gas w EX: dry ice, freeze drying, iodine

A. Phase Changes

B. Heating Curves ö Kinetic Energy w motion of particles w related to temperature ö Potential Energy w space between particles w related to phase changes

B. Heating Curves w. Gas - KE w. Boiling - PE w. Liquid - KE w. Melting - PE w. Solid - KE

B. Heating Curves ö Heat of Fusion w energy required to change from solid to liquid w some attractive forces are broken

B. Heating Curves ö Heat of Vaporization w energy required to change from liquid to gas w all attractive forces are broken w EX: steam burns, sweating, and… the drinking bird w. HEATING CURVE

MATTER Classification of Matter II. Describing Matter w Physical Property w Physical Change w Chemical Property

A. Physical Property ö A characteristic of a substance that can be observed without changing its identity. w can be used to separate mixtures w EX: magnetism, density

B. Physical Change ö A change in the form of a substance without changing its identity. w properties remain the same w reversible w can be used to separate mixtures w EX: dissolving, grinding

C. Chemical Change ö A change in the identity of a substance. w properties change w irreversible w Signs: color change, formation of a gas/solid, release of light/heat w EX: burning, rusting

D. Chemical Property ö A characteristic that indicates whether a substance can undergo a specific chemical change. w EX: flammability, reactivity