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Name:__________________________________________Block:_______Date:__________________________CH. 4 – THE PERIODIC TABLE LABIntroduction:In 1869, aware of the need to organize elements in a meaningful way, Dmitri Mendeleev developed a classification scheme based upon increasing molar mass. Elements that demonstrated similar patterns of chemical behavior were placed into one of eight groups. Members of these groups were displayed in vertical columns of his periodic table. Even though his chart was incomplete, Mendeleev was able to predict the properties of elements yet to be discovered. Over the next two years, Mendeleev published modified versions of his original periodic table.Today’s periodic table accommodates at least 49 additional elements. Although the scheme is based upon increasing atomic number, the arrangement of elements with the chart is similar in organization to the table published by Mendeleev in 1871. Trends in the chemical and physical properties of elements may be seen as periodic function of electron configuration.In this exercise, you will examine several properties of elements and observe how these properties may be interpreted with respect to periodic law. Your knowledge of the modern periodic table and facts about the elements will then allow you to construct the periodic table published by Mendeleev in 1871.Objectives:Relate the electron configuration of an element to its location within the periodic table.Construct graphs of atomic radii and first ionization energies and interpret trends in the data.Construct the periodic table published by Mendeleev in 1871 using a list of clues and your knowledge of the modern periodic table.Materials:pencilrulertextbookProcedure:Complete the prelab questions 1-5 on the next page before starting the lab.Part 1:Locate the upper section of the periodic table illustrated in Part 1 of the Report Sheet. For each of the elements listed, write its noble gas core electron configuration within the appropriate box.Part 2:Using the data listed in Table 1 and the first grid supplied in Part 2 of the Report Sheet, plot the atomic radius of each element against increasing atomic number. The atomic radii shown here are given in nanometers (nm). 1 nm = 1 10-9 mUsing the data listed in Table 1, plot the first ionization energy of each element against increasing atomic number on the second grid supplied in Part 2 of the Report Sheet.Part 3:The positions of the 59 elements found on Mendeleev’s 1871 version of the periodic table are coded for the chart shown in Part 3 of the Report Sheet. The clues found in Table 2 will help you identify the elements. Use your textbook Holt: Chemistry to help identify the coded elements. The index of your text will be very useful in your search. Identify each element and write the name in the correct position on the chart in Part 3.Prelab Questions:Why was the periodic table developed?How was Mendeleev’s scheme for listing elements different from that used in the modern periodic table?What is meant by the term first ionization energy?Which version of Mendeleev’s periodic table will you construct in Part 3 of this exercise?Which two atomic properties will you examine for periodic trends?Table 1:ElementAtomic NumberAtomic Radius (nm)First Ionization Energy (kJ/mol)Hydrogen10.0371312Helium20.0542372Lithium30.152519Beryllium40.111900Boron50.088799Carbon60.0771088Nitrogen70.0701406Oxygen80.0661314Fluorine90.0641682Neon100.0702080Sodium110.186498Magnesium120.160736Aluminum130.143577Silicon140.117787Phosphorus150.1101063Sulfur160.1041000Chlorine170.0991255Argon180.0941519Potassium190.231418Calcium200.197590Table 2:PositionClueElement1Ahas a single electron in the 1s sublevel1Bderived its name from the Latin word for stone, lithos1Ccan be collected as a silver liquid in the electrolysis of table salt1Dhas a first ionization energy of 418 kJ/mol1Ehas a density of 8.96 g/mL1Fis the first alkali metal with a completed 3d sublevel1Gwas originally identified by its Latin name, argentums1His an alkali metal located in period 6 of the modern periodic table1Iderived its name from the Latin word for shining dawn, aurum2Awas used as a target substance in the experiments by Irene Joliot-Curie2Bis an alkaline earth metal located in period 32Cis the metallic component of the substance limestone2Dis a transition metal with 30 protons2Eis represented by the symbol Sr2Fpossesses a nuclear charge of +482Gis an alkaline earth metal found in period 6 of the modern periodic table2His a liquid metal, originally called hydragyrum3Ahas a single electron in the 2p sublevel3Bis a lightweight metal with a molar mass of 26.98 grams3Cis a transition metal with an atomic number of 39PositionClueElement3Dis a metal represented by the symbol In3Eis the first member of the rare earth metals3Fis found in group 3A and period 6 of the modern periodic table4Ais the element whose common isotopic form is the basis of the atomic mass unit4Bhas a second ionization energy of 1577 kJ/mol4Cis located between scandium and vanadium on the modern periodic table4Dis represented by the symbol Zr4Eis a very dense metal with an atomic mass of 207.2 amu4Fis the second member of the actinide series5Ais the most abundant element in the atmosphere5Bhas 3 electrons in the 3p sublevel5Cis a byproduct of fossil-fuel oxidation and represented by the symbol V5Dis a period 4 nonmetal known since 16505Eis a member of both group 5B and period 5 of the modern periodic table5Fwas originally called stibium5Gis located in period 6 of the modern periodic table, beneath niobium5His a metal with atomic number 836Ais the most abundant element in Earth’s crust6Bis a member of group 6A, known during the time of the Roman empire6Cis the first member of group 6B on the modern periodic table6Dis represented by the symbol Se6Ehas 42 protons within its nucleus6Fis a halogen whose crystals sublime6Gwas originally called wolfram6His the fourth member of the actinide series7Ahas an atomic radius of 0.099 nm7Bis represented by the symbol Mn7Cforms a diatomic gas with a molar mass of 160 amu7Dhas a molar mass of 127.6 grams8Ais a group 8B metal known during the time of the Roman empire8Bis an element named after the German word for Satan8Chas an average atomic mass of 59 amu8Dis located between iron and osmium on the modern periodic table8Ehas a nuclear charge of +458Fhas an atomic mass of 106.4 amu8Ghas 114 neutrons within its nucleus8His named after the Latin word for rainbow, iris8Iis an inert metal often used in electrodes and has an atomic number of 78REPORT SHEETPart 1: Representative ElementsPart 2:REPORT SHEET (continued)Part 2 (continued):REPORT SHEET (continued)Part 3: Mendeleev's Periodic Table of the Elements (1871) - Columns (or groups)Analysis and Conclusions:Examine the placement of electron configurations in Part 1 of the Report Sheet. What relationship can be seen in an element's placement within a group and its electron configuration?Examine the graph of atomic radius plotted against increasing atomic number in Part 2. Can a periodic tendency be observed? If so, describe the indicated trend.Which group appears to have members of the largest atomic radii for a given period? Which group has the smallest radii?Examine the graph of ionization energy plotted against increasing atomic number in Part 2. Can a periodic tendency be observed? If so, describe the trend.No members of Group 8A of the modern periodic table can be found on Mendeleev's classification chart. Suggest a reason for their absences.What factor may account for the observed trend in atomic radii as one proceeds across the period? ................
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