CATALYST 1.What is the difference between a substance and a mixture? Give one example of each. 2.What is the difference between a physical change and a chemical change? Give one example of each. 3.Magnesium reacts with oxygen to produce magnesium oxide. If 2.4g of magnesium reacts to make 2.9g of magnesium oxide, how many grams of oxygen react?

ANNOUNCEMENTS Unit 1 exam on Friday 9/21 Study guide and practice problems posted online at haganchemistry.wikispaces.com Grades are up, if you have missing work this needs to be turned in by Thursday Office hours this week Thursday 2:30 – 3:30 Friday 2:30 – 3:30

UNIT 2, DAY 1 UNIT 1 REVIEW AND ATOMIC STRUCTURE

OBJECTIVES Start Unit 2 (45 min) SWBAT define atomic number and mass number, and and explain the role of atomic number in determining the identity of an atom. SWBAT determine its number of protons, neutrons, and electrons given the identity of an atom SWBAT Describe the structure of atoms in terms of protons, neutrons and electrons, and differentiate among these particles Unit 1 Exam Review (40 min) SWBAT review key objectives from Unit 1.

AGENDA Start Unit 2 (45 min total) I Do: Notes on Atomic Structure We Do: Whiteboard Problems You Do: Complete Worksheet, Answer Independent Questions Unit 1 Exam Review (40 min total) I Do: Recap Key Points We Do: Whiteboard Test Problems You Do: Independent Review Problems Closing: Answer EQ

ATOMIC STRUCTURE 3 Subatomic Particles: Protons : Large and Positive (+1), in the Nucleus Neutrons : Large and Neutral (0), in the Nucleus Electrons : Small and Negative (-1), outside the Nucleus

Li 3 7 (Number of protons) Number of protons + neutrons Lithium Number of neutrons = Mass number – atomic number Lithium Electrons Protons3 Neutrons4 Mass number = Atomic number =

Lithium Number of protons Number of electrons = Lithium Electrons3 Protons3 Neutrons4 This is because the atom is neutral. The charges balance out! -3 charge +3 charge No charge

WE DO: WHITEBOARD EXAMPLE TABLE SubstanceSymbol Atomic Number Mass Number Number of Protons Number of Neutrons Number of Electrons Lithium Li37 Carbon C6 6 Fe 2630 *round the mass number to the nearest whole number

YOU DO: INDEPENDENT WORK Complete the remainder of the table independently. If you finish early, continue on to the following problems. P. 119 #23, 28, 29, 30 P. 122 #47, 48, 49

UNIT 1 KEY TOPICS 1.Physical and Chemical Properties and Changes 2.States of Matter: 1.Energy and Definite/Indefinite 3.Elements, Compounds, and Mixtures 1.Differentiate between them 2.Homogeneous vs Heterogeneous 4.Separation Techniques 1.Filtration, Chromatography, Crystallization, Distillation 5.Law of Conservation of Mass 1.Definition 2.Calculating change in mass and giving reasons for change.

WE DO: WHITEBOARDS 1 Review the sample data for the reaction of Baking Soda and Vinegar below. Calculate ∆m. Give one possible reason for the change in mass. Mass of system before change (g) g Mass of system after change (g) 3.84 g ∆m (g)

WE DO: WHITEBOARDS 2 Where would one expect the motion of the particles to be the highest? What state of matter is found at that point? Identify the points where the matter has a definite/indefinite shape and a definite/indefinite volume.

WE DO: WHITEBOARDS 3 Classify the following as a physical or chemical property. Flammability Reactivity Color Mass Classify the following as a physical or chemical change. Melting Ice Mixing Paint Rust Forming List 2 pieces of evidence that a chemical change has taken place.

WE DO: WHITEBOARDS 4 Draw molecular diagrams of an element, compound and a mixture

WE DO: WHITEBOARDS 4 Classify the following as an element, compound, heterogeneous mixture or homogeneous mixture 1.O 2 (Oxygen) 2.Sugar (C 12 H 22 O 11 ) 3.Powerade 4.Hydrochloric Acid (HCl) 5.Steel (Fe, C, Cr) 6.Fruit Salad

WHITEBOARDS 5: True or False. If it is false, correct it. Filtration is commonly used to separate solids from liquids or gases e.g. in air conditioning and in wastewater treatment. Distillation separates mixtures based on how fast they move through a liquid Chromatography uses crystals to separate different substances. Crystallization separates liquids based on the differences in their boiling points

YOU DO: INDEPENDENT REVIEW PROBLEMS Start with the set you struggle most with. 1.P/C Prop and Change: p. 55 #39-41, p. 56 #60-61, p. 57 # 77 2.States of Matter: p. 55 # 45, Rank the states of matter of chlorine in terms of increasing kinetic energy. 3.Elements, Compounds, and Mixtures: p. 55 # 53 (justify by drawing a particle diagram), #48, 50 4.Separation Techniques: p. 41 #17, 19, Is the crystal that forms during crystallization “pure”? Why or why not? 5.Law of Conservation of Mass: p. 57 # 80, 86, p. 59 #11

CLOSING How can I best review for the Unit 1 Exam? Homework: Review for the exam. The remaining review problems are posted on the website along with an answer key.