3 Essential Questions What is the structure of the atom? What are the 3 subatomic particles?What particles make up the nucleus?
4 1. The Atom Atom: the smallest particle of an element (pg:124-125) Nucleus: the center of an atom; also where the protons and neutrons can be found (pg:128)
5 electron clouds nucleus Surrounding the nucleus is a cloud-like region of moving electrons.electron cloudsnucleusAt the center of the atom is a tiny nucleus containing protons and neutrons.
6 A. ProtonProton: positively charged particles in an atom’s nucleus; mass = 1 amu (atomic mass unit)Number of protons identifies the elementNumber of protons and identifies the element = atomic number
7 B. NeutronNeutron: Particles with no charge in the nucleus; mass = 1 amu# of protons + the # of neutrons = mass number/atomic massAdding or taking away neutrons DOES NOT change the atom, it makes different isotopes
8 Isotopes- atoms of the same element that have different numbers of neutrons. Example: Carbon-12 = 6 neutrons, Carbon-13 = 7 neutrons, and Carbon-14 = 8 neutrons (pg: 130)
9 Isotopes or different elements? T has 20 protons and 20 neutronsZ has 20 protons and 21 neutronsT and Z are isotopessame # of protons, different # of neutronsA has 31 protons and 39 neutronsE has 32 protons and 38 neutronsA and E are different elementsdifferent # of protons
10 C. ElectronElectron: negatively charged particles in the electron cloud; mass = 0 amu (very small It takes electrons to equal the mass of 1 proton)# of electrons = # of protons in a neutral atomValence Electron- The electron(s) in the shell farthest from the nucleus
12 Protons (+) Neutron (0) Valence electrons Electron (- ) P+ N A simplified slideP+NNeutron (0)
13 With your partner: Protons Neutrons Electrons Can you name the charge, location and massNeutronsElectrons
14 The electrons are arranged in a particular order The electrons are arranged in a particular order. The electrons fill the energy shells closest to the nucleus first and then fill outward:The first energy shell can hold up to 2 electronsThe second energy shell can hold up to 8 electronsThe third energy shell can hold up to 18 electronsThe fourth energy shell can hold up to 32 electrons
15 Electron Shell Diagram – * First Energy Level2 electronsSecond EnergyLevel 8 electronsThird EnergyLevel 18 electronsFourth EnergyLevel 32 electrons
16 Sub-Atomic Particle Review Atomic mass in atomic mass unitschargelocationProton1 amu+positivenucleusNeutronneutralElectron0 amu_negativeOrbits around nucleus in electron cloud
17 Section 1 Review 7 10 10 8 Oxygen O 1 Hydrogen H 6 Carbon C 7 N Neon Proton numberAtomic numberElementSymbol8OxygenO1HydrogenH6CarbonC7NNeonNe7Nitrogen1010
18 Review 6 12 11 23 14 28 8 16 C Carbon Na Sodium Si Silicon O Oxygen ElementAtomic numberProton numberAtomic mass(rounded)NeutronsElectronsCCarbon612NaSodium1123SiSilicon1428OOxygen816
19 Organizing the elements Chapter 4.2Cornell Notes
20 4.2 Essential QuestionsHow is the Periodic Table of the Elements (PTE) arranged?
21 1. Mendeleev-Russian Chemist who looked for patterns of properties of the elements.-He grouped the elements according to the patterns and by increasing atomic mass.-This allows us to predict the properties of missing elements.
22 2. Atomic WeightThe average of all the masses of all the isotopes of an element
23 3. Using the periodic table The properties of an element can be predicted from its location on the periodic tableElements are arranged in order of increasing atomic weight
24 4. How to read the Periodic Table Atomic Number- number of protonsAtomic SymbolFirst letter always capitalized, second neverCAtomic Mass- protons +neutrons612.011
25 4. How to read the Periodic Table (partner review) Li36.941
26 5. Periods Horizontal rows (pg. 134-135) The properties gradually change as you move left to right across the Periodic Table.Indicates the number of electron shells
32 Essential QuestionsWhere are metals, nonmetals and semi metals on the PTE?What are the properties of metals, nonmetals and semimetals?What are the properties of elements in each family?
33 Metals, Nonmetals, and Semimetals • Metals and nonmetals are separated by a stair-step line on the right side of the table.• Metals are found to the left of the line and nonmetals are found to the right of the line.• Elements that border the line on both sides are called semi-metals.
35 A. Metals 1. Found on the left of the periodic table. 2. Have only a few electrons in outer shell.3.Most are solid, shiny, good conductors of heat and electricity, malleable, are ductile.4. Alkali metals – Family/Group 15. Alkaline earth metals – Family/Group 26. Transition metals – Families/Groups 3-12
36 B. Nonmetals 1.Found on the right side of periodic table 2. Most are dull, not malleable or ductile, not good conductors of heat or electricity.3.Valence electron shell is mostly or completely full
37 C. Semi-Metals (metalloids) 1.Found along the zig-zag (stair step) line on the periodic table; also called metalloids2. They are semi-conductors that have properties of both metals and non-metals.3.The outer electron shell is about half full.
38 With your partnerCan you identify where the metals, non metals and semimetals are on the PTEWhat are the properties of metal?What are the properties of a nonmetal?What are the properties of a semimetal?
39 Valence Electrons Electrons that are in the outer shell Valence Electrons determine reactivityA full shell is stableThe valence shell is complete with 8 electrons
40 reactivity Empty or Full Half full or half empty non reactive (inert)Close to full or close to emptyvery reactiveHalf full or half emptynot as reactive
41 Boron Family Alkali Metals Halogen FamilyInert / Nobel GasesLanthanidesActinidesOxygen FamilyNitrogen FamilyTransition MetalsBoron FamilyCarbon FamilyAlkaline Earth MetalsAlkali Metals
42 A. Alkali Family (1 Valence Electron) The most reactive metalsShiny and softCan be cut with a knife
43 B. Alkaline Earth Metals (2 Valence Electrons) Very ReactiveSilver colored metals, more dense than family #1
44 C. Transition Metals Have 1-2 Valence electrons Includes many common metals such as copper, iron, gold, and silver
45 D. Boron Family (3 valence electrons) Reactive Solids
46 E.Carbon Family (4 Valence electrons) Reactivity variesAll are solidsCarbon based molecules make up all living things
47 F.Nitrogen Family (5 valence electrons) Reactivity variesNitrogen is the most common element in the atmosphere
48 G. Oxygen Family (6 valence electrons) Reactive
49 H. Halogen Family (7 valence electrons) -These are theMOST REACTIVE NONMETALS-Some are used as cleaners
50 I.Inert Gases (Noble Gases) (8 valence electrons) Stable – Not reactive!!All are nonmetals, and all are gasesHelium only has 2 valence electrons because it only HAS 2 electrons total
51 Lanthanide and Actinide Families (2 valence electrons) These are a part of the transition element family
52 Liquids, gases and semi metals The majority of elements are solids (so we are not labeling those)Find and mark (be creative) the liquidsFind and mark (be creative) the gasesDarken the stair step line for metalloids and outline the boxes of elements that are semi- metals