Pre-Class Wednesday 9-11-13 List three things that make up an atom. Hint: you can find them in chapter 4.

Atoms and the Periodic Table Chapter 4

History of the Atom Democritus (Greek) Thomson Model (British) Uncuttable atom Grain of sand/salt Thomson Model (British) Electrons were stuck to a ball of positive charge Rice pudding or chocolate-chip cookie dough Rutherford Model (British) Nucleus separate from electrons Most of the atom’s mass at nucleus Electrons orbit around it Bohr Model (Danish) Electrons orbit nucleus, much like planets orbit the Sun

Electron Cloud Model The electron cloud surrounds the nucleus The electron cloud is where electrons that orbit the nucleus are most likely to be found Not fixed orbits, but they do go around the nucleus Each energy level or band is broken into orbitals (s, p, d, and f)

Structure of the Atom Proton Neutron Electron Quark Positive charge 1.67 x 10-27 kg Neutron No charge Same mass as proton Electron Negative charge 9.11 x 10-31 kg Quark Up, down, top, bottom, strange, charm Each has charge (+/-) and color (blue, red, green) Structure of the Atom

Particles of matter that make up protons and neutrons are _____. Pre-Class Thursday 9-12-13 Particles of matter that make up protons and neutrons are _____. Electrons Isotopes Atoms Quarks

Make A Quark Objective Procedures Questions Learn more about quarks. Use the table to make as many particles as you can. Name each one of them. Remember: the total charge has to be +1, -1, or 0. Questions Do you think all of your particles are possible? Explain.

Blue: metals Green: metalloids Yellow: nonmetals

Step 1 in using the Periodic Table Atomic number is equal to the number of protons in an atom. Atomic number is equal to the number of electrons in an atom. Mass number = atomic number + number of neutrons Atomic weight is approximately equal to the mass number.

How many neutrons are in a Rhenium (Re) atom? 75 111 186 261 Pre-Class Friday 9-13-13

Isotope An element that has the same number of protons, but different number of neutrons For example: Carbon-12  6p+, 6no, 6e- Carbon-14  6p+, 8no, 6e-

Electron Configuration Represents the atomic structure of elements Shows the number of electrons and their relative distance from the nucleus Uses the Bohr Model (Planetary Model) Orbital paths of electrons are called energy levels or energy shells 1st energy level can hold 2 electrons 2nd energy level can hold 8 electrons 3rd energy level can hold 18 electrons 4th energy level can hold 32 electrons

Drawing an Electron Configuration Write Chemical Symbol. Circle it. (defines the nucleus) Find atomic number. (determines number of electrons) Draw circles. (period # determines ring #) Put 2 electrons in 1st ring, 8 in 2nd ring, etc. until atomic number is reached Hint: Use the Periodic Table to help you.

Draw the Electron Configuration of: Li Ca N Ar Al He

Draw the electron configuration for Sulfur. Pre-class Monday 9-16-13 Draw the electron configuration for Sulfur.

Properties of Metals Good conductors of electricity Good conductors of heat All but one are solid at room temperature Malleable: can be hammered into sheets Ductile: can be stretched out into wires Most are shiny (reflective)

Alkali Metals Family 1 Softer than most metals React rapidly, almost violently One electron in outer shell

Alkaline Earth Metals Family 2 Reacts easily with other elements Contains two electrons in outer shell Each burns with brilliant colors (used in fireworks)

Transition Elements Groups 3-12 These elements are “transitioning” from groups 1 & 2 to groups 13-18 Do not react as easily as other metals Iron Triad Coinage metals Lanthanides Actinides

Which group or family is known as the coinage metals? Pre-Class Tuesday 9-17-13 Which group or family is known as the coinage metals?

Properties of Nonmetals Poor conductors of electricity Poor conductors of heat Gas or a brittle solid at room temperature Not malleable Not ductile Dull in appearance, not shiny

Nonmetal-only Families Group 17 Halogens Has 7 electrons in outer shell Group 18 Noble Gases Has a full outer shell

Pre-Class Wednesday 9-18-13 How many neutrons does Hydrogen have?

Metalloids A.K.A. semiconductors Displays characteristics of metals and nonmetals Under certain conditions, they can conduct heat and electricity

Moles? A mole is a unit of measurement Abbreviated “mol” One mole measures 6.022 x 1023 items e.g. 1 mole of M&Ms = 6.022x1023 M&Ms called Avogadro’s constant (number) The atomic weight in the Periodic Table is also known as the molar mass

Changing your mass units To go from mol to grams, multiply the molar mass by the number of mol To go from grams to mol, divide the number of grams by the molar mass To find the molar mass, divide the mass in grams by the mass in mol g g/mol mol

A chemical symbol represents the _____ of an element. Pre-Class Thursday 9-19-13 A chemical symbol represents the _____ of an element. Name Structure Type Reaction

A Personal Periodic Table Objective: To make your own periodic table from everyday items. Procedures: In groups of three, use items found in backpacks, pockets, purses, etc. and organize them into several columns based on their similarities. Ignore duplicate items. Questions: Explain the system you used to group your items. Were there any items on the list that did not fit into any of your columns?

Are the squares A and B the same color? Pre-Class Friday 9-20-13 Are the squares A and B the same color?

What’s in a name? Groups of 2 or 3 Choose an element group (cannot be repeated) Fill-in the chart on the paper Answer the questions at the bottom

The table gives the abundance of some metals in the Earth’s crust. List the metals in order from most to least abundant. List the metals in order of price from cheapest to the most expensive. Metal Abundance (%) Price ($/kg) Aluminum 8.2 1.55 Chromium 0.01 0.06 Copper 0.006 2.44 Gold 0.0000004 11,666.53 Iron 5.6 0.03 Silver 0.000007 154.97 Tin 0.0002 6.22 Zinc 0.007 1.29 Cost of Metal

Questions If the price of metal depends on its abundance, you would expect the order to be the same on both lists in the chart. Compare the lists. How well do they match? The order of reactivity of these metals, from most reactive to least reactive, is: aluminum, zinc, chromium, iron, tin, copper, silver, and gold. Use this information to explain any exceptions to the lists. How much of each could you buy for $100?