Chemistry Day 9 Monday, September 12, 2016 Do-Now Title: BrainPOP: Atoms 1. Complete the do-now on the worksheet provided. Do not turn over until instructed to do so. Finished? Take out your planner and table of contents. Announcements This week: UCLA interns Grades submi7ed Thursday!! Trade in dojo points! 5 points = Cardinal points, treat, or pen/ pencil 15 points = HW stamp Most each quarter = mystery prize Planner: Grades submitted this Thurs! Ch. 4 Quiz Mon 9/19 Unit test week of 10/3 (100 pts!) Table of Contents #1: 14. BrainPOP: Atoms FLT I will be able to preview the main ideas of atomic theory by completing BrainPOP: Atoms Standard HS-PS1-8: Develop models to illustrate the changes in the composioon of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioacove decay BrainPOP: Atoms Watch the BrainPOP video A:er the video, answer the ques>ons in your group every member must copy down the same answer The group with the most correct answers à +5 dojo points each h7ps://www.brainpop.com/science/ma7erandchemistry/atoms/ 1
CW 1. Complete the worksheet as a group. Raise your hand when you think you have all answers correct. First group to have all answers correct = dojo points! 2. Complete ToC assignments or quietly read Ch. 4 Chemistry Day 9 Tuesday, September 13 Wednesday, September 14, 2016 Do-Now Title: Inquiry Demo 1. Write down today s FLT 2. What do you think atoms are? 3. What do you think atoms are made of? 4. Draw what you think an atom looks like. Label your drawing. 5. What tools do you think you would need in order to discover or study atoms? 6. Underneath your do-now, write demo observations and questions Finished? Take out your planner and table of contents. Announcements This week: Grades! Trade in dojo points! Make sure you re doing the following: GeSng stamps Retaking low scores Checking the weebly/remind Checking powerschool Planner: Finish Ch. 4 Review WS by Friday Materials: Demo Table of Contents #1: 15. Inquiry Demo 16. 4.1 Cornell Notes 17. Ch. 4 Review WS 2
Demo I m going to take a sponge, put some rubbing alcohol on it, and then put it in a sealed glass jar I will then turn the jar upside down on top of some dry ice Underneath your do-now, write a predic>on about what you THINK will happen Demo Watch the demo If you re close to the demo, you must wear goggles Write down what you see happening or what you think you see happening. Discuss with your group if needed. Demo Now, write down three ques>ons you have about the demo. Demo Discuss your ques>ons with your group. Decide as a group which ques>on is the best or the most interes>ng, and everyone should write it on their paper. What do you think we saw? FLT I will be able to describe early ideas about the atom by completing 4.1 Notes Standard HS-PS1-8: Develop models to illustrate the changes in the composioon of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioacove decay 3
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 Ch. 4 Notes What is an Atom? 4.1: Defining the Atom What is an Atom? Atom = the smallest par>cle of an element that retains its iden>ty in a chemical reacoon An atom is extremely small - what would be needed in order for people to discover it? A history of the atom Ancient Greece: Philosopher Democritus did not discover the atom, but he was one of the first to suggest their existence. 4
A history of the atom Democritus described atoms as indivisible and indestruc>ble. Was he correct? Could he support his ideas?! There was no evidence to support Democritus ideas (yet) John Dalton - 1776-1844 John Dalton was a chemist who studied gases, pressure, and the existence of atoms. John Dalton - 1776-1844 John Dalton = supported Democritus idea with scien>fic evidence. Came up with the early ideas for atomic theory... Dalton s Atomic Theory 1. All elements are composed of tiny indivisible particles called atoms Dalton s Atomic Theory 2. Atoms of the same element are identical. The atoms of any one element are different from those of any other element. Dalton s Atomic Theory 3. Atoms of different elements can mix or combine in simple whole-number ratios to form compounds 5
Dalton s Atomic Theory 4. Chemical reactions occur when atoms are separated, joined, or rearranged. Atoms of one element, however, are never changed into atoms of another element as a result of a chemical reaction. Dalton s Atomic Theory Note: Not all of Dalton s ideas were correct...as we will see when we talk about modern atomic theory :) How Can We Study Atoms? Atoms can be seen using extremely high powered microscopes, such as scanning tunneling microscopes. 4.1 Section Quiz 1. The ancient Greek philosopher credited with suggesting all matter is made of indivisible atoms is A. Plato B. Aristotle C. Democritus D. Socrates 4.1 Section Quiz 1. The ancient Greek philosopher credited with suggesting all matter is made of indivisible atoms is A. Plato B. Aristotle C. Democritus D. Socrates 4.1 Section Quiz 2. Dalton s atomic theory improved earlier atomic theory by a. teaching that all matter is composed of tiny particles called atoms b. theorizing that all atoms of the same element are identical c. using experimental methods to establish scientific theory d. Not relating atoms to chemical change 6
4.1 Section Quiz 2. Dalton s atomic theory improved earlier atomic theory by a. teaching that all matter is composed of tiny particles called atoms b. theorizing that all atoms of the same element are identical c. using experimental methods to establish scientific theory d. Not relating atoms to chemical change 4.1 Section Quiz 3. Individual atoms are observable with a. the naked eye b. a magnifying glass c. a light microscope d. a scanning tunneling microscope 4.1 Section Quiz 3. Individual atoms are observable with a. the naked eye b. a magnifying glass c. a light microscope d. a scanning tunneling microscope Pair-Share-Respond 1. What is an atom? 2. What did Democritus believe? 3. List the four parts of Dalton s atomic theory. CW Use your textbook to answer the Ch. 4 Review Worksheet questions. You Ch. 4 begins on page 101 Finish at least the first page tonight You may work on stamp sheet assignments Chemistry Day 10 Thursday, September 15 Friday, September 16, 2016 7
Do-Now Title: Atoms Kahoot!/4.2 S.A. 1. Write down today s FLT 2. Draw what an atom would look like according to Democritus 3. What did Dalton provide that Democritus did not? 4. Identify one way that both Dalton and Democritus were mistaken about atoms 5. List one part of Dalton s atomic theory. 6. Underneath your do-now, if you re playing Kahoot on your phone, write your initials. If you re playing on paper, number 1-14. Finished? Take out your planner and table of contents. Announcements Expect progress reports Monday Next Wednesday Back to School Night 6:30-8:00 Gym = Eng, Math Media Ctr = VAPA, Language Cafeteria = Social Sci, Science Cafeteria Service = PE/Dance Don t have your powerschool login? See any teacher, counselor, or AP for your login informa>on Announcements Unit Test will cover Ch. 1, 13, 4, and 25 Want to be exempt from semester finals? Maintain a 70%+ on your tests No missing labs Have 4 or fewer ToC ssignments total Planner: Get ALL stamps ToC due week of 9/26 Study! Ch. 4 Quiz next week Table of Contents #1: 18. Atoms Kahoot/4.2 S.A. 19. 4.2 Notes WS FLT I will be able to describe early atomic models by completing 4.2 Notes Standard HS-PS1-8: Develop models to illustrate the changes in the composioon of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioacove decay 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 8
4.2: Structure of the Atom What is an atom made of? As it turns out, atoms ARE divisible, as three main subatomic particles were discovered: # Protons # Abbreviation: p + # Neutrons # Abbreviation: n 0 # Electrons # Abbreviation: e - Subatomic Particles Protons = Charge: +1 charge Location: particles found in the nucleus of an atom Mass: Relative mass = 1 Subatomic Particles Neutrons = Charge: uncharged Location: particles found in the nucleus of an atom Mass: Relative mass = 1 Subatomic Particles Electrons = Charge: -1 charge Location: particles found orbiting around the nucleus Mass: Insignificant mass How???? If atoms were so difficult to discover given their tiny size, how were subatomic particles discovered?? 9
What does this mean? What do we know about the two ends of magnets? What happens when we push magnets close together (two different things can happen)? Why? The discovery of the electron... In 1897, J.J. Thomson discovered the electron He conducted experiments using electric currents passing through gases at low pressure The discovery of the electron... These electric currents produced a cathode ray (a glowing beam) that traveled from the cathode (-) to the anode (+) What does this look like? In summary Because the movement of the stream was from the cathode (negative end) to the anode (positive end), there must be some part of the atom that is NEGATIVELY charged Protons & Neutrons 1886: Goldstein performed a similar experiment and observed that there were positively-charged particles traveling toward the cathode. These positive particles would later be called protons. 10
Protons & Neutrons 1932: Chadwick discovered the neutron. This particle was hard to discover because it is neutral, but it has a significant mass (about equal to a proton) that Chadwick studied. Our Particles Okay, so there are three particles... How did scientists figure out the atom s composition? Developing Atomic Theory Dalton thought atoms were simply indivisible spheres plum pudding model: J. J. Thomson thought there were just (+) and (-) particles scattered within an atom. But then someone else discovered the nucleus... Ernest Rutherford In 1911, Rutherford s experiments involved shooting a beam of POSITIVELY CHARGED alpha particles at a thin sheet of gold foil He noticed that the vast majority of alpha particles passed through the foil easily. However, there were a FEW particles that were DEFLECTED back (did not go through). Rutherford s Conclusions Most of the particles passed through --> Most of an atom is empty space A few (very few) particles were deflected back --> since the alpha particles are positive, there must be a tiny, dense, positivelycharged center in an atom 11
Our atomic model so far... Atoms are composed of three main subatomic particles: p +, n 0, e - Protons and neutrons are located in the nucleus of the atom, which is a very small, but dense (contains a LOT of mass in a small volume) Electrons are VERY tiny, negatively charged, and orbit around the nucleus. They make up most of the VOLUME of the atom. But of course......we still haven t talked about modern atomic theory and models yet :) 1. Which of the following is NOT an example of a subatomic particle? a. proton b. molecule c. electron d. neutron 1. Which of the following is NOT an example of a subatomic particle? a. proton b. molecule c. electron d. neutron 2. The nucleus of an atom consists of a. electrons only b. protons only c. protons and neutrons d. protons and electrons 2. The nucleus of an atom consists of a. electrons only b. protons only c. protons and neutrons d. protons and electrons 12
3. Most of the volume of the atom is occupied by the a. electrons b. protons c. protons and neutrons d. neutrons 3. Most of the volume of the atom is occupied by the a. electrons b. protons c. protons and neutrons d. neutrons 4. Which scientist discovered the neutron? a. Chadwick b. Dalton c. Thomson d. Rutherford 4. Which scientist discovered the neutron? a. Chadwick b. Dalton c. Thomson d. Rutherford Pair-Share-Respond 1. Identify our three subatomic particles list their charge, mass, and location. 2. Explain what was missing from Thomson s plum pudding model 3. What were Rutherford s two conclusions? CW 1. Underneath your Kahoot/Do-Now, answer questions 8-11, 13-14 on page 108 2. Stamps or study Ch. 4 13