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Unit 3: Periodic Table Lab Packet Unit 13: Periodic Table Lab Packet DO NOT LOSE THIS PACKET. IT WILL BE SUBMITTED AT THE END OF THE UNIT FOR ALL LAB CREDIT. Please keep track of when each lab is assigned and the due date by which it should be completed. Model: An Electron Dot Diagram of the Main Group Elements 2-1 Task Below the symbol for each element, write an electron configuration for the elements in the model. Lithium has been done for you. Key Questions 1. How are members of the same column (group) similar in terms of the number of valence electrons? 2. Which group contains the least number of valence electrons? 3. Which group contains the largest number of valence electrons? 4. Which period (row) contains three occupied shells? 5. Within a group, which period, top or bottom is likely to contain atoms with the larger radius? Explain your answer. 6. In terms of the number of valence electrons, describe one cyclic property that can be observed in the model. 1 Exercise Complete all of the information below for each of the atoms with the following ground state electron configurations: Electron configuration 2-8-3 2-8-8-1 2-6 2-8-18-7 2-8-18-32-18-8 Element symbol Group number Period or Row number Nuclear# of protons charge # of valence electrons Electron dot diagram (atom) Ion’s charge (oxidation state) # Ion’sof electrons symbol lost including or gained. Indicatecharge if lost or gained. (Hint: use the # of electrons lost or chargegained. of Indicate the ion toif figurelost or this out. gained. Questions: 1 a. Which of the above elements have fewer than 4 valence electrons? b. What type of ions do these elements form? Explain how these ions form in terms of valence electrons. c. Are these elements metals or nonmetals? 2 a. Which of the above elements have greater than 4 valence electrons? b. What type of ions do these elements form? Explain how these ions form in terms of valence electrons. c. Are these elements metals or nonmetals? 2 METALS NONMETALS METALLOIDS 1. Have luster 1. Are dull 1. Have luster 2. Are malleable and ductile 2. Are brittle 2. Are brittle 3. Conduct heat and electricity 3. Do not conduct heat or electricity very well. 3. Semi-conductors 4. Lose electrons to form ions 4. Prefer to gain electrons to form an ion. 4. Can gain or lose electrons 5. Low electronegativity and ionization 5. High electronegativity and ionization energies to form an ion. energies. 5. Moderate electronegativities and ionization energies. 3 Name: ____________________________________________ Date: _____________________ Lab # _____: Metals, Nonmetals and Metalloids Background: More than 75% of the elements on the Periodic Table are metals. They are recognizable by certain characteristics. You will examine several different elements and determine if they are metals or nonmetals based on the properties observed. Procedure: 1. At each of the stations, record the name of the element into your data table. 2. Using your reference tables look up the atomic symbol and draw the Lewis dot diagram of the atom. 3. Observe the color of the element and record it. 4. Rub the sample of the element with steel wool to see if you can make it shiny and lustrous. Record your result as shiny or dull. 5. Use the conductivity tester to see if the sample conducts electricity (Make sure the tester is switched “on” and put both ends of the tester to a sample, but do not let the two metal prongs touch each other). If the light goes on, it conducts electricity. Record your result. 6. Try to bend the sample gently. If it bends, record it as malleable. If it does not bend, record it as brittle. Data Table: Name Symbol Lewis Dot Color Luster Conducts Malleable/ Diagram electricity Brittle 1 2 3 4 5 6 7 8 4 Name: ____________________________________________ Date: _____________________ Lab # _____: Metals, Nonmetals and Metalloids Teacher Demonstration Elements (at the front desk): Station # Name Symbol Lewis Dot Color Luster Conducts Phase at Diagram electricity Room Temperature 9 Iodine NO NO 10 Bromine NO NO 11 Mercury YES YES Analysis Questions: 1. From your notes, what are the properties of metals? 2. Using the information from Question # 1, which samples that you tested were metals? Explain why you classified these elements as metals using your observations from the lab. 3. Where are metals and nonmetals located on the Periodic Table with respect to the Boron “staircase”? 4. Are there more metals or nonmetals on the Periodic Table? 5. Where are the metalloids located on the periodic table? Name the metalloids. 6. Using your notes, what are the characteristics of a metalloid? 7. In terms of the number of valence electrons, how do the electron dot diagrams of metals compare to the electron dot diagrams of nonmetals? 8. What type of ion does Sodium, Magnesium and Aluminum form? A cation or an anion? Support your answer with evidence from the periodic table. 9. Which type of ion does Fluorine, Oxygen, and Chlorine form? A cation or an anion? Support your answer with evidence from the periodic table. 5 Name: ______________________________________ Date: __________________ Lab #____: Trends of the Periodic Table Purpose: To graph several properties of selected elements and observe the trend as you move across a period or down a group within the periodic table. Materials: Reference Table for Chemistry, pencil, pen Pre-lab Questions: Define each of the following terms: a. Atomic Radius: b. First Ionization Energy: c. Electronegativity: d. Nuclear charge: Procedure: 1) On the graphs provided, graph the properties listed for the elements in Group 16 (Oxygen, Sulfur, Selenium, Tellurium and Polonium) and then again for those in Period 3 (Sodium, Magnesium, Aluminum, Silicon, Phosphorus, Sulfur, Chlorine and Argon). 2) The x-axis has been completed for you. Please label an appropriate y-axis before plotting. 3) Graphs to plot: a) atomic radius b) first ionization energy c) electronegativity. Find information on Table S. 4) For each graph, circle and connect the points. You will then answer questions about the observed trend for each graph and explain why this trend occurs. Atomic Radius Trends Radius (pm) Radius Atomic Atomic (pm) Radius O S Se Te Po Na Mg Al Si P Cl Ar Elements in Group 16 Elements in Period 3 6 First Ionization Energy Trends First Ionization Energy (kJ/mol) First Ionization Energy (kJ/mol) Energy First Ionization O S Se Te Po Na Mg Al Si P Cl Ar Elements in Group 16 Elements in Period 3 Electronegativity Trends Electronegativity Electronegativity O S Se Te Po Na Mg Al Si P Cl Ar Elements in Group 16 Elements in Period 3 7 Questions and Conclusions 1) State the Periodic Law: 2) What keeps the valence electrons tethered to an atom and prevents them from easily escaping? (Hint: Use your knowledge of atomic structure and subatomic particles) Looking at your graphs, state the change in each property as you go down a group and across a period. 3) Atomic Radius Graph Analysis a. Observed trend down a group: b. Observed trend across a period: c. Explain, in terms of atomic structure, why the atomic radius increases down a group. d. Explain, in terms of atomic structure, why the atomic radius decreases across a period. 4) First Ionization Energy Graph Analysis a. Observed trend down a group: b. Observed trend across a period: c. Explain, in terms of atomic structure, why the ionization energy decreases down a group. d. Explain, in terms of atomic structure, why the ionization energy increases across a period. 8 5) Electronegativity Graph Analysis a. Observed trend down a group: b. Observed trend across a period: c. Explain, in terms of atomic structure, why the electronegativity decreases down a group. d. Explain, in terms of atomic structure, why the electronegativity increases across a period. 6) Explain why the transition metals were skipped for the period 3 graphs showing trends in ionization energy, electronegativity and atomic radius. 7) Why does having a low first ionization energy and low electronegativity cause a metal to be very reactive? 8) Why does having a high first ionization energy and high electronegativity cause a nonmetal to be very reactive? 9 Name___________________________________________________ Date:______________ Activity: What can be determined by examining the Periodic Table of Elements? Background: By the mid-1800s, 60 elements were known. Scientists had quite a bit of information about these elements, but the information was not organized, so it was not very useful. In 1869, a Russian scientist named Dmitri Mendeleev made a chart of the know elements. Since that time, more elements have been discovered and added to the chart. The chart is called the PERIODIC TABLE OF ELEMENTS, which is used worldwide. In the periodic table, elements are arranged in order of their atomic numbers. With a couple of exceptions, atomic numbers are in the same order as atomic masses. That is, the lightest element has the lowest atomic number and the heaviest element has the highest atomic number. ** Each row is called a _________________ ** Each column is called a ________________________ **Each group is identified by a number ** Elements can be divided into two main types ______________and ________________ There are more metals than nonmetals, and metals are located to the left of the “stair-step” line. Hydrogen can behave as a metal or nonmetal, depending on the situation, but is considered a nonmetal. ANSWER THE QUESTIONS ABOUT THE PERIODIC TABLE. USE YOUR TABLE AS A REFERENCE 1. List the periods by number______________________________________ 2. List the groups by number ______________________________________ A). Fill in the following table using elements from Period 3.
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