MODERN CHEMISTRY TEXTBOOK: CH. 1 Matter & Its Properties

Basic Building Blocks of Matter

Anything that takes up space and has mass Takes up space  volume Certain amount of stuff  mass How does one make stuff? Start with the ATOM! What is matter?

The study of matter and the changes it undergoes Composition Structure Properties Energy changes What is chemistry?

Atom – smallest unit of an element that has the chemical identify of that element Element – Pure substance that cannot be broken down into simpler, stable substances So only 1 kind of atom (a few or many) Compound – Pure substance that can be broken into simpler, stable substances must have 2 different kinds of atoms Elements vs. Compounds

Is this an element?

Elements & Compounds can be found in many different states of matter or phases What’s the Difference between States of Matter Video Substances only move from one phase to another by physical means. States of Matter

Shape volume What physical characteristics can you observe to determine a substances state of matter? Definite volume Definite shape Definite volume Indefinite shape Indefinite volume Indefinite shape

Plasma: high-temperature state of matter in which atoms lose most of their electrons

Physical property – characteristic of a substance that can be observed/measured without altering substances identify Physical change – change in which identify of substance is not altered Physical vs. Chemical Properties

Physical changes will always require the absorption/release of energy (Heat or light)

Chemical Property – ability to undergo changes that transforms substance into a new substance Chemical change – change in which 1 or more substances are converted into different substances What if a substance’s identity is altered?

Chemical Changes Reactants substances that react Products substances that are formed yields

Evidences of Chemical Change Formation of a gas Formation of precipitate Evolution of energy (heat/light) Color change

Energy is always involved in physical and in chemical changes Law of Conservation of Energy: energy can be absorbed or released, but is never destroyed or created.

PhysicalChemicalExtensiveIntensive 1. Color 2. Combustibility 3. Hardness 4. Luster 5. Flammability 6. Reacts with acids to form H 2 7. Mass 8. Density 9. Melting Pt. 10. Can neutralize a base 11. Ductility 12. Odor 13. Weight 14. Malleability 15. Tendency to corrode 16. Length ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔

_______ 8. Wood rotting. _______ 9. When placed in H 2 O, a sodium pellet catches on fire as H 2 gas is liberated and sodium hydroxide forms. _______ 10. Grass growing in a lawn. _______ 11. A tire is inflated with air. _______ 12. Food is digested in the stomach. _______ 13. Water is absorbed by a paper towel. _______ 14. Sugar dissolved in water. _______ 1. Hydrochloric acid reacts with potassium hydroxide to produce a salt, water and heat. _______ 2. A pellet of sodium is sliced in two. _______ 3. Water is heated and changed to steam. _______ 4. Iron rusts. _______ 5. Evaporation _______ 6. Milk sours. _______ 7. Ice melting. C P P P P P P P C C C C C C

GROUPING MATTER TO MAKE IDENTIFICATION EASIER Classification of Matter

Blend of 2 or more kinds of matter, each that retain its own identify and properties Mixed together physically Can be separated physically (no chemical rxn’s needed) Homogeneous (solutions): uniform in composition Salt – water solution Heterogeneous : not uniform throughout Clay-water mixture Mixtures

Suspensions – particles in solvent so large that they settle out unless constantly stirred/agitated Colloids – particles of intermediate size that stay dispersed throughout a mixture. Often appears cloudy Use Tyndall Effect to identify (shine light source through mixture and particles become visible in beam of light) Heterogeneous Mixtures

Fixed composition Every sample of pure substance has exactly the same properties and composition Ex: Water is always 11.2% hydrogen and 88.8% oxygen by mass (determined from periodic table) Pure Substances

Column A Pure substance or mixture Column B Element or Compound/Heterogeneo us or Homogeneous 1. Chlorine 2. Water 3. Soil 4. Sugar water 5. Oxygen 6. Carbon dioxide 7. Rocky road ice cream 8. Alcohol (in water) 9. Pure air 10. Iron Pure Mixture Pure Mixture Pure Mixture PureElement Compound Element Compound Element Homogeneous Heterogeneous Homogeneous Heterogeneous Homogeneous

SECTION 1.3 Introduction to the Periodic Table

Why don’t elements and their symbols always look like they correspond to each other? What is the periodic table?

Periods Groups

The vertical columns of the periodic table are called groups, or families. Each group contains elements with similar chemical properties. The horizontal rows of elements in the periodic table are called periods. Physical and chemical properties change somewhat regularly across a period. Groups & Families

4 Basic Categories of Elements

elements to the left of the zigzag line Properties of metals Most solids at room temperature Malleable (hammered or rolled into thin sheets) Ductile (drawn into a thin wire) conduct electricity and heat well Metals

Gold, copper, aluminum Metals

right of the zigzag line an element that is a poor conductor of heat and electricity Properties of nonmetals many are gases solids are brittle poor conductors of heat and electricity Nonmetals

(a) carbon, (b) sulfur, (c) phosphorus (d) iodine Nonmetals

surrounds zigzag line an element that has some characteristics of metals and some characteristics of nonmetals Properties of metalloids all metalloids are solids at room temperature semiconductors of electricity **Aluminum is not a metalloid – it’s a metal! Metalloids

Elements in Group 18 Properties of Noble Gases Generally unreactive (i.e. “inert”) Gases at room temperature Glow if electricity is passed through them Noble Gases