Chemistry. Monday, September 25 th Tuesday, September 26 th, 2017

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1 Chemistry Monday, September 25 th Tuesday, September 26 th, 2017

2 Do-Now Title: Nuclear Notation Review 1. Answer the do-now questions on your worksheet 2. Do not begin working on the other questions until instructed to do so Finished? Take out your planner and table of contents.

3 Announcements ToC must be turned in by Friday Recall To be exempt from semester final you cannot miss more than four TOTAL stamps from our ToC s You also need a 70%+ on unit tests and no missing labs/quizzes Retake old quizzes and trade-in dojo points Back to school night Thursday Minimum day Friday

4 Planner: Last day for stamps: Thursday ToC due by Friday (turn in to HW box) Read Ch. 19 (all) Retake Ch. 3 Quiz Table of Contents #1: 24. Nuclear Notation Review 25. Ch. 19 CN Part A

5 Review

6 CW 1. Take minutes to complete the review WS in your groups Mass number for Br is 80, and the mass number for Pb is When finished, start reading Ch We will begin our notes shortly

7 FLT I will be able to describe the three main types of nuclear radiation by completing Ch. 19 CN A Standard HS-PS1-8: Develop models to illustrate the changes in the composi;on of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioac;ve decay

8 Ch. 19 Part A: Radiation Title your notes & add assignment # Complete Cornell-style Copy down all bolded ideas Noise level 0 Raise hand to question/comment Be prepared to pair-share-respond

9 Ch. 19 Part A: Radiation

10 Guiding Questions What are the two nuclear forces? What are the three types of radioac;ve decay? Which is the deadliest type of radioac;ve decay? How do you protect yourself from Alpha radia;on?

11 Review Atomic Models

12 Nucleons and Nuclear Forces

13 Subatomic Par;cles In 1932, James Chadwick discovered the neutron This was important in improving the protonelectron atomic model New model: The proton-neutron nucleus

14 Proton-Neutron Model

15 Subatomic Par;cles We now have three subatomic par;cles: Protons p + Electrons e - Neutrons n 0 Nucleons = subatomic parncles located in the nucleus of atoms (p + and n 0 ) Nucleons are composed of smaller par;cles called quarks

16 Forces There are two main forces at play in our nucleus: Electromagne;c force (proton-proton repulsion) Strong force (nucleons s;ck together)

17 Forces Not all nuclei are stable Posi;vely-charged protons can repel each other Strong Nuclear Force = binds p + and n 0 together in the nucleus

18 Unstable Nuclei Strong force = holds nuclei together over short distances Larger nuclei can be more unstable

19 Nuclear Stability

20 Nuclear Stability Strong Nuclear Force This force can only act over very short distances It is the strongest axrac;ve force (137 ;mes more than electromagne;c) Over extremely short distances, the strong nuclear force overrides the repulsion of the electromagne;c force Looking at the ra;o of protons to neutrons can help us determine the stability of the nucleus

21 The region on a graph which indicates all stable nuclei when the number of neutrons are compared to the number of protons for all stable nuclei Band of Stability

22 Nuclear Stability Larger nuclides tend to be more unstable All nuclides with more than 83 protons (bismuth) are unstable Most nuclides want a 1:1 of neutrons: protons Heavier nuclides need more neutrons

23 Pair-Share-Respond 1. What are nucleons? 2. What force holds nucleons together? 3. What types of nuclei tend to be unstable?

24 Radioactivity

25 Radioactivity How does an unstable nucleus release energy?

Context Marie Curie (1867-1934) helped discover new elements (Polonium and Radium), as well

26 Context Marie Curie ( ) helped discover new elements (Polonium and Radium), as well as radioac;ve elements Curie studied materials that gave off rays, which she called radioac;vity

27 Radiation Radia;on = Rays & par;cles emixed by a radioac;ve source

28 Radiation Radioisotopes = unstable isotopes whose nuclei undergo changes to become more stable

29 Radioactivity An unstable nucleus decays into a new nucleus by changing its number of protons spontaneously If the number of protons changes, is it the same element anymore?

30 Radioactivity RadioacNve decay = unstable nucleus releases energy/emits radianon

31 Types of Radiation

32 Types of Radiation What are the three main types of nuclear radiation?

33 Main Types of Radiation 1. Alpha (α) Radiation 2. Beta (β) Radiation 3. Gamma (Υ) Radiation

34 Alpha Radiation Alpha radiation = Emits alpha particles (helium) Mass number decreases by 4, atomic number decreases by 2

36 Ex/ Alpha Radiation

37 Beta Radiation Beta Radiation = Emits a beta particle (electron) Mass number stays the same. Atomic number increases by 1.

39 Ex/ Beta Radiation

40 Gamma Radiation Gamma radiation = Emits a high-e photon(gamma ray). Tends to accompany other nuclear decay processes

42 Types of Radiation Alpha parncles are the least penetranng. Gamma rays are the most penetranng.

43 Figure 4.2: The penetra;ng power of radia;on John Wiley and Sons Publishers

44 Are there other types of decay? α-par;cle produc;on Spontaneous fission β-par;cle produc;on Positron produc;on γ-ray produc;on

45 Positron Production Positron = positively charged anti-electron

46 Review 1. Certain elements are radioactive because their atoms have a. more neutrons than electrons. b. an unstable nucleus. c. a large nucleus. d. more neutrons than protons.

47 Review 2. An unstable nucleus releases energy by a. emitting radiation. b. thermal vibrations. c. a chemical reaction. d. giving off heat.

48 Review 3. Which property does NOT describe an alpha particle? a. 2+ charge b. a relatively large mass c. a negative charge d. low penetrating power

49 Review 4. When a radioactive nucleus releases a high-speed electron, the process can be described as a. oxidation. b. alpha emission. c. beta emission. d. gamma radiation.

50 Pair-Share-Respond 1. What are radioisotopes? 2. What are our three main types of radia;on? 3. Which type is the most dangerous? 4. What is emixed in beta decay? 5. What is emixed in alpha decay?

51 CW 1. Underneath your notes, complete the questions from page 694: #1-5, 8, 9, Finished? Read Ch. 19 Carefully

52 Chemistry Wednesday, September 27 th Thursday, September 28 th, 2017

53 Do-Now Title: Video Notes: Nuclear Processes 1. Write down today s FLT. 2. When can you retake quizzes? 3. What can you trade in your dojo points for? List specific examples with how many points they cost 4. Why do some nuclei undergo decay? 5. Identify the three main types of decay, and list them in order from least penetrating to most penetrating 6. Use a pro-talk sentence frame to make a claim about nuclei, radiation, or decay. 7. Write Video Notes underneath your do-now Finished? Take out your planner and table of contents.

54 Announcements ToC due Finish retakes AYend tutoring as needed Must have calculators next week Unit test MulNple choice secnon and response secnon

55 Turn in ToC Planner: Study for Unit Test (Ch. 1, 3, 13, 19) Bring calculators next week Table of Contents #2: 1. Video Notes: Nuclear Processes

56 Video Notes Let s review some of the concepts we covered, as well as look at some topics we will be covering soon

57 Video Notes 1. What are the four fundamental forces? 2. Dis;nguish between nuclear fusion and fission. 3. An atomic bomb uses which of these processes? 4. Why is radioac;ve decay useful to us when studying history? 5. One addi;onal fact

59 Video Notes 1. What are the four fundamental forces? 2. Dis;nguish between nuclear fusion and fission. 3. An atomic bomb uses which of these processes? 4. Why is radioac;ve decay useful to us when studying history? 5. One addi;onal fact

60 Introduction to Half-Life

61 Introduction to Half-Life Unstable nuclei decay Do they all decay at the same rate?

62 Introduction to Half-Life The half-life of a nuclide is the Nme it takes for ½ of the sample to decay A^er each half-life, half of the remaining atoms have decayed into a new element We can represent this graphically What would that look like?

63 Introduction to Half-Life

64 Mini-Lab

65 Ch 19 Radioactive Half-Life Lab You will use m&m s or skixles to represent isotopes What are isotopes? You must place paper towels over your sta;on/table Please do not eat while performing the lab Contaminated candies should be thrown out at the end Tables must be wiped down at the end for sanita;on purposes

66 Ch 19 Radioactive Half-Life Lab Write your starnng number of candies You will need to count out 100 candies without contaminanon Use two cups to shake your candies Pour them out across the paper towels

67 Ch 19 Radioactive Half-Life Lab Candies facing up = remaining isotopes à keep these for the next round Record the remaining number in your data table Candies facing down = decayed isotopes à set these aside, as they will not be used anymore

68 Ch 19 Radioactive Half-Life Lab Gather up your remaining candies and shake them up. Repeat the steps unnl all isotopes have Decayed.

69 Time 1 million years Class data 2 million years 3 million years 4 million years 5 million years 6 million years 7 million years 8 million years 9 million years 10 million years 11 million years 12 million years

70 Ch 19 Radioactive Half-Life Lab Graph your results on the back of the page. Don t forget to label your axes. Also graph the class average data using a different color pen. You should label each or have a key Use the class average graph to answer the quesnons below.

71 CW Turn in labs when finished J Did you answer in complete sentences? Study Ch. 19 Test next week! Turn in ToC if it s ready

72 Chemistry Friday, September 29 th Monday, October 2 nd, 2017

73 Planner: Finish WS + Study for Ch. 19 Quiz Unit Test (Ch. 1, 3, 13, 19) 10/9-10/10 Next lesson: calculators Table of Contents #2: 2. Return of the Brainstorm 3. Ch. 19 CN B 4. Nuclear Radiation WS

74 Announcements Class dojo adjustment: 5 points: pen, pencil, snack (limit one per day) 10 points: new reference sheet 15 points: stamp Unit test Tues/Wed Finish Ch. 19 Thurs/Fri Ch. 19 Quiz + Unit Review Mon/Tues Unit Test

75 Announcements A note on the ToC ToC s with all stamps = +5 dojo points Missing stamps are totaled at the end of each semester to help determine who is exempt from the final or not Unstamped assignments can be turned in with an Incomplete assignment form with the ToC for parnal credit à staple everything together

76 FLT I will be able to write balanced nuclear equations by completing Ch. 19 Notes B Standard HS-PS1-8: Develop models to illustrate the changes in the composi;on of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioac;ve decay

77 Notes Protocol Title your notes & add assignment # Complete Cornell-style Copy down all bolded ideas Noise level 0 Raise hand to question/comment Be prepared to pair-share-respond

78 Ch. 19 CN B: Nuclear Transformation

79 Guiding Questions What is nuclear fusion? What is nuclear fission? How do we write and balance nuclear equations?

80 Recall

82 Radiation When a nucleus spontaneously breaks down by emitting radiation, the process is called radioactive decay.

84 Alpha Emission Emits alpha particles, which contain two protons and two neutrons and has a double positive charge. Alpha emitters are radioisotopes that decay by emitting alpha particles α par;cle = 4 He 2

85 Beta Emission Emit beta particles The neutron breaks apart into a proton, which remains in the nucleus, and a fast-moving electron, which is released. This increases the atomic number by one. β - par;cle = 0 e -1

86 Gamma Emission Nuclei often emit gamma rays along with alpha or beta particles during radioactive decay.

87 Nuclear Equations

88 Nuclear Equations Radioactive decay can be shown in a nuclear equation using the symbols for the original radioactive nucleus, the new nucleus, and the radiation emitted. Nuclear Equations à Balanced when both sides are equal to each other Radioactive nucleus à new nucleus + radiation

89 Nuclear Equations In nuclear reactions, atoms transmutate Transmutation = Conversion of an atom of one element into an atom of another element Transmutation can occur by radioactive decay or when bombarded by other particles

90 Copy This Example:

91 BALANCING NUCLEAR EQUATIONS 1. Sum of mass numbers must be = on each side (le^ superscripts) 2. Sums of atomic numbers/charges (le^ subscripts) on each side of the equanon must be =. Examples: 238 U 4 He Th Pb 0 β Bi

92 Try these: Complete the nuclear equanons and state the type of decay: At 213 Bi +? He Th 0 β +? Pa Tl 0 e +? Pb 82

93 Fission & Fusion

94 Nuclear Fission When the nuclei of certain isotopes are bombarded with neutrons, they undergo fission Fission = the splitting of a nucleus into smaller fragments/nuclei.

95 Nuclear Fission Chain reaction = Fission produces neutrons, causing other atoms to undergo fissions, which in turn releases more neutrons, etc.

96 Nuclear Fusion The energy released by the sun results from nuclear fusion. Fusion = when nuclei combine to produce a nucleus of greater mass.

97 Nuclear Fusion Fusion reactions, in which small nuclei combine, release much more energy than fission reactions, in which large nuclei split.

98 Pair-Share-Respond 1. What is a transmutation? 2. Distinguish between nuclear fission and nuclear fusion. 3. Which type releases more energy? 4. Complete the balanced equation:

99 Reminder for today s WS α-par;cle produc;on Spontaneous fission β-par;cle produc;on Positron produc;on γ-ray produc;on

100 FYI: Electron Capture vs. Beta Decay

101 CW Complete the WS Use periodic table If written in isotope notation (example: Carbon-14 or C-14) change to shorthand notation first Study by reading notes, the textbook, or quizzing your group members

Chemistry Day 10. Monday, September 17 th Tuesday, September 18 th, 2018

Chemistry Day 10. Monday, September 17 th Tuesday, September 18 th, 2018 Chemistry Day 10 Monday, September 17 th Tuesday, September 18 th, 2018 Do-Now Title: Brainstorm: Unit 1 1. Write down today s FLT 2. Draw what an atom looks like according to Democritus and Dalton 3.