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WKS 4.1 - the Scientists (1 Page) Pre-AP Chemistry Unit 4 Practice Packet Name _____________________________ WKS 4.1 - The Scientists (1 page) The List of Scientists (Can be used more than once!!!) Johann Dobereiner John Newlands Dimitri Mendeleev Henry Moseley Glenn Seaborg John Dalton J.J. Thomson Ernest Rutherford Neils Bohr Erwin Schrodinger Write the name of the scientist by his contribution….. 1. Who performed the Cathode Ray Tube Experiment? 2. Electrons were in energy levels. The further an electron was from the nucleus, the higher its energy. 3. Arranged the elements according to atomic number 4. Recognized the relationship between properties of “triads” of elements and their atomic mass. 5. Postulated the quantum (wave) mechanical model 6. The atom as mostly space and that all of the positive charge was located in a very small central nucleus 7. Synthesized transuranic elements 8. Published a version of the periodic table that was arranged according to atomic mass. wisely included blanks for unknown elements that I predicted would be discovered 9. Elements were arranged according to atomic mass that every 8th element seemed to have similar properties 10. “Billiard Ball” theory 11. Discovered that electrons were negative? 12. Who developed the first theory of the atom? 13. Who developed the planetary model? 14. Who performed the Gold Foil Experiment? 15. Who developed the Plum Pudding Model? 16. List the conclusions made from the Gold Foil Experiment. Page 1 of 9 Pre-AP Chemistry Unit 4 Practice Packet Name _____________________________ WKS 4.2 – Element Search (1 page) Use a highlighter or a pen to find the full names of the following elements. Try it without a periodic table first to check your knowledge of symbols and names! SYMBOL SYMBOL SYMBOL SYMBOL SYMBOL SYMBOL Al Ca He Hg Se Xe Sb C H Ne Si Zn Ar Cs I Ni Ag As Cl Fe N Na Ba Cr Kr O Sr Be Co Pb P S B Cu Li Pt Sn Br F (be careful!) Mg K W Cd Au Mn Rn U M U I T N O R T S E L E N I U M Z C G X E N O N A A C M K X A A N S U I N A R U Z A O U Y X O I H Y G A O Y C A D M I U M S X I R L L P L T I C Y K O N N G E K U O E N I R O L H C M Z P D A K D L O G E K M I M N N C X I Z L C I U B I E A E R R I A X S U T U N G S T E N Y P U I R G I R L O K R N C N I Z N O N E Z L K R Y M S A N E G E G Z O E I U M U I N A R U Y A E R E S C E D O M E E N S S P O C M E N I M O R B K R A O G A N O N B N E E X R D U N F Y M Y B K E R T B O K K N M O S P Y T H F L I T H I U M N B S O A R E O I U R G G E L C E A T E T B Y I O A C P L T C D N N O E O D R A U E L E I O R N T R I Z T I A E R I N E N I D O I I N U L U U D P I N S L N D R A T N D R U F L U S M V O N C E Y U E I X P N P K A C E S I U M R S I L V E R N R M S O D I U M L L Y E N I R O U L F R A H E A K C R S I R H C U P H O S P H O R U S Y N O M I T N A A R U S I B Page 2 of 9 Pre-AP Chemistry Unit 4 Practice Packet Name _____________________________ WKS 4.3 – The Periodic Table (1 page) Match each element in Column A with the best matching description(s) from Column B. COLUMN A COLUMN B 1. ___________strontium A. halogen 2. ___________chromium B. noble gas 3. ___________iodine C. alkaline earth metal 4. ___________argon D. metalloid 5. ___________rubidium E. alkali metal 6. ___________silicon F. transition element Give the correct symbol for each element described by the following: 7. Noble gas in the third period 8. Group 14 element in the fourth period 9. Halogen in the second period 10. Group 4 element in the fifth period 11. Alkali metal in sixth period 12. Group 13 element in fourth period 13. Group 11 element in sixth period 14. Alkaline earth metal in the second period 15. Properties of elements are most similar to other elements — A. in the same group C. with the same number of neutrons B. in the same period D. with a smaller atomic mass 16. Which of the following is a NOT property of metal? A. tend to be malleable C. have high melting points B. have low boiling points D. are conductors of electricity 17. An unknown element found at a crime scene has the following characteristics: It is a liquid, it does not conduct electricity, and has low melting and boiling points. What type of element is this substance most likely? A. Metal C. Non-metal B. Semimetal D. Transition metal 18. In which set do the elements exhibit the most similar chemical properties? A. Li, Na, and K C. Hg, Br, and Rn B. N, O, and F D. Al, Si, and P 19. An unknown element has the following characteristics: it is malleable, is extremely reactive, has a grey/white color, and conducts electricity. What type of element is this substance most likely? A. Alkali metal C. Transition metal B. Semimetal D. Alkaline earth metal Page 3 of 9 Pre-AP Chemistry Unit 4 Practice Packet Name _____________________________ WKS 4.4 – Components of the Atom (1 page) ATOMIC MASS CALCULATIONS: If specific masses are given for the isotopes, use the specific masses. If no specific masses are given, you are allowed to use the mass numbers for the mass of the isotope. NO WORK = NO CREDIT! 1. A natural sample of boron consists of two isotopes. One has an exact mass of 10.0129 amu and its percent abundance is 19.91%. The other isotope of mass 11.0093 amu, has a percent abundance of 80.09%. Calculate the atomic mass. (10.81 amu) 2. Calculate the percent abundances of copper-63 and copper-65 if the atomic mass is 63.546 amu and the exact masses of the isotopes are 63Cu = 62.93 amu nd 65Cu = 64.93 amu. Assume no other isotopes exist. (63Cu = 69.2% and 65Cu = 30.8%) 3. Silicon is found in nature combined with oxygen to give sane, quartz, agate, and similar materials. The element has three stable isotopes. Calculate the atomic mass. (28.08 amu) Exact Mass % Abundance 27.97 92.23 28.97 4.67 29.97 3.10 4. Naturally occurring lithium consists of two isotopes, 6Li and 7Li, and has an atomic mass of 6.941 amu. Which isotope is more abundant? What are the percent abundances of the two lithium isotopes? Their masses are 6.01512 and 7.01600, respectively. (more 7Li, 6Li 7.49% and 7Li 92.51%) 5. Naturally occurring silver has two isotopes. Isotope A has a relative mass of 106.9051 and an abundancy 51.82%. Isotope B has a relative mass of 108.9047. Calculate the atomic mass of silver from this data. (107.87 amu) Page 4 of 9 Pre-AP Chemistry Unit 4 Practice Packet Name _____________________________ WKS 4.5 – Components of the Atom Continued (1 page) 1. Define an isotope: 2. For isotopes of the same element, state whether they differ or are the same in the following: a. mass? c. number of neutrons? b. number of protons? d. number of electrons? 3. Neon has two isotopes: neon-20 and neon-22 a. Which isotope has the greater mass? ______ c) Which isotope has more protons? ______ b. Which isotope has more neutrons? ______ d) Which isotope has more electrons? ______ Answer the following questions: _____1. The +2 ion for vanadium (#23) would have how many electrons? _____2. The –3 ion atomic number 15 would have how many electrons? _____3. The 1+ ion of potassium (#19) would have how many electrons? _____4. How many protons would the 3+ ion of aluminum (#13) have? _____5. What would be the ratio of protons to electrons in the 1– ion of chlorine (#17)? _____6. How many MORE electrons than protons would the 2– ion of selenium (#34) have? -1 _____7. The nuclear symbol for an unknown ion is 53 X . What element are we talking about here? _____8. How many electrons are there in the 1+ ion of Cs-136 (#55)? _____9.
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