Monday 9/29/14. Which of the following are isotopes of copper, Cu? Explain your reasoning. A. 63 Cu B. 197 Au C. 63 Cu D. 87 Cu E. 34 Cu F.

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1 Monday 9/29/14 Which of the following are isotopes of copper, Cu? Explain your reasoning. A. 63 Cu B. 197 Au C. 63 Cu D. 87 Cu E. 34 Cu F. 65 Cu

2 Monday 9/29 Students A and C come get a small white board and pen from my desk. Together with your seat partner, solve the following problem: 99.6% of Argon is Argon-40, 0.063% is Argon-38 and 0.34% is Argon-36. Calculate the average atomic mass for Argon. Show your work!

3 Try again! Chromium is found as 4 isotopes, 4.35% is 50 Cr, 83.79% is 52 Cr, 9.5% is 53 Cr and 2.36% is 54 Cr. Show how to calculate the average atomic mass of chromium.

4 Monday, 9/29/14 Agenda 1. Warm-up 2. Zaption 3. Lesson 14: Isotopia Stable and Radioactive Isotopes Homework To Do Element Quiz Retakes Prior Knowledge Lunch Tuesday In NB pg. 29, TB pgs EQ: What affects nuclear stability? Quiz on Block Day

5 Review Zaption 7 p+, 7 n0, 10 e- ( = -3) The job of keeping the protons in the nucleus together is a challenging one for the neutrons. Why do you think this is the case? Because the positive protons want to repel each other. Because the protons naturally repel each other. The beam of electrons used to generate such images has a Negative charge (electrons) Why do you think the electrons continue to fly around the nucleus and don t fly out into space? The law how things are attracted to each other. The nucleus (+) is holding them in place. The electrons are attracted to the protons in the nucleus. They are attracted to the positive charge of the protons.

6 Review Zaption Are carbon-12 and nitrogen-14 isotopes? No, not same element. However, they are isotopes of different elements. Are carbon-12 and carbon-14 isotopes? Yes, same element, different mass. Carbon-12 has 6 protons (atomic number = 6) 6 neutrons = mass 12 protons 6 Mass of each subatomic particle Electron too small to matter! Where is all the mass of an atom located? Nucleus (neutrons, protons) Carbon-14 has 6 protons (atomic number = 6) 8 neutrons = mass 14 protons 6

7 How do you find out the number of isotopes an element has? I still wonder how to find the amount of isotopes of an element. Are isotopes all different versions of an atom or just the irregular ones? I still wonder why elements have isotopes what are protons and electrons and neutrons made out of? why electrons do not affect mass. Although their What would happen if the neutrons weight is deemed insignificant, wouldn't a large weren't there? amount of electrons sway mass by at least a little? If some atoms are negatively or Also, I had questions in how electrons move positively charged then does that affect around in their paths, I saw something on Cosmos how big the atom is based on the orbital (Neil DeGrass Tyson's) science show that said of the neutron? Because the force that is they teleport or change energy i don't know it pulled on the electron by a proton (lets didn't make a lot of sense to me. say a positive atom) is greater than its orbit then that would mean that the orbit I want to figure out how to do the cutting is smaller and closer to the nucleus? aluminum equation, I made it too complex with I still have questions about what logs. determines the structure of bonded I am still confused as to why there are isotopes in atoms. general because they do not change characteristics. I'm still wondering about specifics of orbitals.

8 Formative Assessment Attach to NB pg. 12 as a flappy over the Prior Knowledge Activity.

9 Essential Question What types of isotopes do the various elements have? SWBAT Interpret a graph of naturally occurring isotopes Describe the general nuclear composition of a stable nucleus Key Terms radioactive isotope Differentiate between a stable isotope and a radioactive isotope

10 Prepare for the activity Isotopia - Stable and Radioactive Isotopes Work in pairs You should each have a copy of the periodic table.

11 Naturally occurring isotopes The graph of naturally occurring isotopes gives us an idea of how many different isotopes of the elements are found in nature. The words atom, isotope, and element are interrelated.

12 Nuclear Composition of Isotopes Nearly all atoms have at least one neutron for every proton in the nucleus. Many isotopes have more neutrons than protons.

13 unstable = radioactive A handful of the isotopes on the chart are unstable. Some elements have naturally occurring radioactive isotopes. The isotopes of the elements after Bismuth (atomic number 84 and up) are all radioactive. Radioactive isotope: any isotope that has an unstable nucleus and decays over time.

14 Wrap-up What types of isotopes do the various elements have? Each element found in nature has somewhere between 1 and 10 isotopes. The neutron-to-proton ratio is an important factor in determining the stability of the nucleus of an isotope. Atoms with small masses have a neutron-to-proton ratio of about 1:1. The most massive atoms have a neutron-to-proton ratio of about 3:2 (or 1.5:1) Some elements have isotopes that are radioactive. The nuclei of radioactive isotopes are unstable and decay over time.

15 ExitTix.com Use the chart to determine how many neutrons you would need to make a stable element with 79 protons. Write the hyphen notation for the isotope.

16 Homework due Quiz Block Day Open notebook