Self-Study Guide Electrons and The Periodic Table

Transcription

1 Self-Study Guide Electrons and The Periodic Table Make sure you can define the following terms related to waves: 1. EM Spectrum 2. Wavelength 3. Frequency 4. Amplitude Make sure you can put the following EM waves in order in terms of energy: X-rays, gamma rays, microwaves, visible light, Radio waves, TV waves, infrared, ultraviolet Make sure you can identify the following parts of the Periodic Table: 1. Alkali Metals 2. Alkaline Earth Metals 3. Halogens 4. Noble Gases 5. Transition Metals 6. Inner Transition Metals Page 3

2 Video: Chemistry: The Periodic Table and Periodicity Please Answer the following question while you watch the video 1. Where are metals, metalloids and non-metals found on the periodic table? Metals - Metalloids Non-metals 2. What is the order of the elements on the periodic table? 3. What is a characteristic of all metals? 4. What is the column headed by Fluorine called? 5. Why are elements in the same column considered families? 6. Who invented the first periodic table? What element number is named after him? 7. How did Mendeleev arrange the periodic table? 8. What is true of elements in the same column? 9. What happens to the metallic properties or nature of an element as you move left to right across the periodic table? 10. What element did Mendeleev predict before it was discovered? What is the real name of this element today? What number is it on the periodic table? page 4

3 Development of the Periodic Table State what each of the following scientists contributed to the development of the modern periodic table: 1. J.A.R. Newlands 2. J.W. Dobereiner 3. Dmitri Mendeleev 4. H.G.J. Moseley 5. State the periodic law. How is this different from Mendeleev s arrangement of the periodic table? 6. Calculate the average of the atomic mass of lithium and potassium. How does this compare with the actual atomic mass for sodium? 7. Calculate the average of the atomic mass of sodium and rubidium. How does this compare with the actual atomic mass for potassium? 8. Why does the law of triads predict the atomic mass of sodium with great accuracy but is inaccurate in predicting the mass of potassium? page 5

4 Labeling the Periodic Table m k a b c d e f g h i j On the line at the left, write the letter of the appropriate location of each group of elements on the periodic table above. Some letters will be used more than once. 1. carbon family 2. alkaline earth metals 3. inner transition metals 4. halogens 5. d-block elements 6. oxygen group 7. alkali metals 8. f-block elements 9. noble gases 10. p-block elements 11. nitrogen family 12. s-block elements 13. transition metals 14. group of one semimetal and four metals [Ar] 4s 2 3d 5 is an abbreviated (or shorthand) electron configuration. 15. What does the [Ar] stand for? 16. What does the 4 signify? 17. What do the s or the d indicate? 18. What do the superscripted 2 or 5 indicate? page 6

5 Identify each of the following elements as a metal (M), nonmetal (NM), or a metalloid/semimetal (SM): 19. Sodium 20. Silicon 21. Neon 22. Calcium 23. Nitrogen 24. Tungsten What is the name of the following families? 25. Group Group Group Group What properties distinguish metals from nonmetals? 30. What does an electron configuration tell you about an element? Relating Electron Configuration to the Periodic Table 1. Write the electron configuration for the atoms with the following atomic numbers: 3: 11: 19: 2. What do these configurations have in common? 3. What would you expect about the relative properties of these elements? 4. In what family are these elements located on the periodic table? page 7

6 5. Write the electron configuration for the atoms with the following atomic numbers: 9: 17: 35: 6. What do these configurations have in common? 7. What would you expect about the relative properties of these elements? 8. In what family are these elements located on the periodic table? Ionic Charge and the Periodic Table 1. Write the electron configuration for the atoms with the following atomic numbers: Ca: Ca 2+ : 2. Why is the +2 ion the one that commonly forms? 3. In what family is Ca located on the periodic table? 4. What charge would ions of other elements in this family tend to form? Why? 5. Write the electron configuration for the atoms with the following atomic numbers: S: S 2 : 6. Why is the 2 ion the one that commonly forms? 7. What charge would ions of other elements in this family tend to form? Why? page 8

7 Periodic Trends: Atomic Radius and Ionization Energy The size of atoms is measured in terms of atomic radius, in units such as nanometers or angstroms (1 Å = 1 x m). The ionization energy, or energy needed to remove an electron from an atom, is typically measured in kilojoules per mole of atoms. 1. Define Atomic Radius. 2. Explain the relationship of between the relative size of an atom and its ion based on the charge of the ion. 3. What is the charge each of the following elements will have when it achieves a complete set of valence electrons? O Na F N Ca Ar The radius of the first few elements of group 17 have the following values: F (element 9) 0.64 Angstroms Cl (17) 0.99 Angstroms Br (35) 1.14 Angstroms I (53) 1.33 Angstroms Graph these radii versus the atomic number in the grid provided: 1.5 Atomic Radius (Angstroms) Atomic Number 4. What is the relationship between atomic radius and atomic number? Explain why this trend is seen. page 9

8 The radius of the first seven elements of period 3 have the following values: Na (11) 1.86 Angstroms Mg (12) 1.60 Angstroms Al (13) 1.43 Angstroms Si (14) 1.17 Angstroms P (15) 1.10 Angstroms S (16) 1.04 Angstroms Cl (17) 0.99 Angstroms Graph these radii versus the atomic number in the grid provided: 1.5 Atomic Radius (Angstroms) Atomic Number What is the relationship between atomic radius and atomic number? Explain why this trend is seen. The first ionization energies of the first three elements of group 2 have the following values: Be (4) 900 kj/mol Mg (12) 736 kj/mol Ca (20) 590 kj/mol Graph these first ionization energies versus the atomic number in the grid provided: Ionization Energy (kj/mol) Atomic Number What is the relationship between ionization energy and atomic number? Explain why this trend is seen. page 10

9 The first ionization energies of the elements of period 2 have the following values: Li (3) 519 kj/mol Be (4) 900 kj/mol B (5) 799 kj/mol C (6) 1088 kj/mol N (7) 1406 kj/mol O (8) 1314 kj/mol F (9) 1682 kj/mol Ne (10) 2080 kj/mol Graph these first ionization energies versus the atomic number in the grid provided: Ionization Energy (kj/mol) Atomic Number What is the relationship between ionization energy and atomic number? Explain why this trend is seen. Periodic Trends Which pair of atoms or ions has the larger atomic radius? Circle the correct answer. 1. Li or K 2. Ca or Ni 3. Ga or B 4. O or C 5. Cl or Br 6. Be or Ba 7. Si or S 8. Fe or Fe K + or O Ba 2+ or I 11. Al 3+ or P K + or Cs Fe 2+ or Fe F or S 2 Which pair of atoms or ions has the larger first ionization energy? Circle the correct answer. 15. Na or O 16. Be or Ba 17. Ar or Cl 18. Cu or Cr 19. I or F 20. K or V 21. Ca or Ra 22. W or Bi 23. K or K I or I 25. In general, what can you say about ionization energy when comparing the values for metals and nonmetals? 26. Why is there such a large jump in ionization energy between the second and third ionization energies for magnesium? page 11

10 27. Define electronegativity. What is the periodic trend for electronegativity? Challenge Problems Periodic Table 1. The ions S 2, Cl, K +, Ca 2+, Sc 3+ have the same total number of electrons as the noble gas argon. How would you expect the radii of these ions to vary? Would you expect to see the same variation in the series O 2, F, Na +, Mg 2+, Al 3+ in which each ion has the same total number of electrons as the noble gas neon? Why or why not? 2. Explain why some chemists consider Hydrogen to be a semimetal. Periodic Table - Word Scramble Use the clues provided to help you unscramble the letter to form words related the development of atomic structure. The letters in the circle spell out, in order, the name of a famous chemist. CLUES 1. Na, Mg, Cr and Fe for example 6. A series 2. Charged particle 7. Like Neon 3. An unreactive element 8. Sr 2+, Rb + and Kr, for example 4. K to Kr, for example 9. A transition metal 5. Cl and I, for example 1. S A L M T E 2. N C L R E T E O 3. N G O R A 4. E P O D I R 5. N H E L O A G S 6. A L A E N H N D T I 7. O L B E N 8. I N E E T L O S I C C R O 9. N A V I M A U D Name page 12