2. II. Periodic Table

3. J Deutsch 2003 2 The placement or location of elements on the Periodic Table gives an indication of physical and chemical properties of that element. The elements on the Periodic Table are arranged in order of increasing atomic number. (3.1y) Mendeleev’s original table was according to mass. This was changed when Moseley discovered atomic number.

4. J Deutsch 2003 3 The number of protons in an atom (atomic number) identifies the element. 6 C The sum of the protons and neutrons in an atom (mass number) identifies an isotope. Common notations that represent isotopes include: 14 C, carbon-14, C-14. (3.1g) Atomic number is written on the bottom left. Mass number is written on the upper left.

5. J Deutsch 2003 4 Regents Question: 01/03 #9 An atom of carbon-12 and an atom of carbon-14 differ in (1)Atomic number (2)Atomic mass (3)Nuclear charge (4)Number of electrons

6. J Deutsch 2003 5 Regents Question: 06/02 #4 All the isotopes of a given atom have (1)the same mass number and same atomic number (2)the same mass number but different atomic numbers (3)different mass numbers but the same atomic number (4)different mass numbers and different atomic number

7. J Deutsch 2003 6 Regents Question: 06/02 #9 Atoms of the same element that have different numbers of neutrons are classified as (1)Charged atoms (2)Charged nuclei (3)Isomers (4)Isotopes

8. J Deutsch 2003 7 The average atomic mass of an element is the weighted average of the masses of its naturally occurring isotopes. (3.1n) IsotopeMassAbundanceCalculation 12 C1298.89%12 x.9889 = 11.87 13 C131.108%13 x 0.01108 = 0.1440 Atomic Mass (weighted average) 12.01 amu

9. J Deutsch 2003 8 Atomic mass is found on the Periodic Table of the Elements

10. J Deutsch 2003 9 Regents Question: 01/03 #36 Hydrogen has three isotopes with mass numbers of 1, 2, and 3 and has an average atomic mass of 1.00794 amu. This information indicates that (1)Equal number of each isotope are present (2)More isotopes have an atomic mass of 2 or 3 than 1 (3)More isotopes have an atomic mass of 1 rather than 2 of 3 (4)Isotopes have only an atomic mass of 1

11. J Deutsch 2003 10 Regents Question: 01/03 #3 In which list are the elements arranged in order of increasing atomic mass? (1)Cl, K, Ar (2)Fe, Co, Ni (3)Te, I Xe (4)Ne, F, Na

12. J Deutsch 2003 11 Elements can be classified by their properties and located on the Periodic Table as metals, nonmetals, metalloids or semimetals (B, Si, Ge, As, Sb, Te), and noble gases. (3.1v) Metals on the left Nonmetals on the right Metalloids or semimetals

13. J Deutsch 2003 12 Regents Question: 01/03 # 37 Which list of elements contains two metalloids? (1)Si, Ge, Po, Pb (2)As, Bi, Br, Kr (3)Si, P, S, Cl (4)Po, Sb, I, Xe

14. J Deutsch 2003 13 Elements can be differentiated by their physical properties. Physical properties of substances, such as density, conductivity, malleability, solubility, and hardness, differ among elements. (3.1w) A physical property is one which does not change the identity of the substance when tested. Density=mass/volume

15. J Deutsch 2003 14 All elements are solid at room temperature except for the following: Liquids  Mercury (Hg) - the only liquid metal at room temperature  Bromine (Br) - the only liquid nonmetal at room temperature Gases  Hydrogen (H)  Oxygen (O)  Nitrogen (N)  Fluorine (F)  Chlorine (Cl)  All of group 18 (noble gases) Helium (He), Neon (Ne) Argon (Ar), Krypton (Kr), Xenon (Xe), Radon (Rn)

16. J Deutsch 2003 15 Comparing the physical properties of metals and nonmetals  Silvery gray color except copper and gold  Solid at room temperature except mercury  Good conductors of heat and electricity  Malleable – can be hammered into shapes (thin sheets)  Ductile – can be pulled into wires  Many different colors –Sulfur – yellow –Chlorine – green –Bromine – orange –Iodine - purple  Many different states (phases) –H, N, O – gas –Br – liquid –S, C, I – solid  Poor conductors of heat and electricity (except carbon)  Brittle – breaks when hit Metals Nonmetals

17. J Deutsch 2003 16 Regents Question: 06/03 # 6 Which is a property of most nonmetallic solids? (1) high thermal conductivity (2) high electrical conductivity (3) brittleness (4) malleability

18. J Deutsch 2003 17 Elements can be differentiated by chemical properties. Chemical properties describe how an element behaves during a chemical reaction. (3.1x) When testing a chemical property, the substance may change into another substance. The number of atoms an element combines with is an important chemical property: NaClCaCl 2 AlCl 3 CCl 4 HClH 2 ONH 3 CH 4

19. J Deutsch 2003 18 Some elements exist in two or more forms in the same phase. These forms differ in their molecular or crystal structure, and hence in their properties. (5.2f) These are called allotropes. Allotropes of oxygenAllotropes of carbon Oxygen ( O 2 )Graphite Ozone ( O 3 )Diamond Buckminsterfullerene

20. J Deutsch 2003 19 For Groups 1, 2, and 13-18 on the Periodic Table, elements within the same group have the same number of valence electrons (helium is an exception) and therefore similar chemical properties. (3.1z)

21. J Deutsch 2003 20 Regents Question: 06/03 # 53-54 Given: Samples of Na, Ar, As, Rb Which two of the given elements have the most similar chemical properties? Explain your answer in terms of the Periodic Table of the Elements. Na and Rb They are in the same group

22. J Deutsch 2003 21 Group numbers and family names  Group 1Alkali Metals –Very reactive metals, always found as compounds in nature –1 valence electron - lose 1 electron to form +1 ions  Group 2Alkaline Earth Metals –Reactive metals, always found as compounds in nature –2 valence electrons - lose 2 electron to form +2 ions  Group 17Halogens –Reactive nonmetals –7 valence electrons - gain 1 electron to form –1 ions  Groups 18Noble Gases –Not reactive – do not form ions –Filled, stable valence shell (8 electrons except He which has 2)

23. J Deutsch 2003 22 Regents Question: 01/03 #6 Which Group of the periodic Table contains atoms with a stable outer electron configuration? (1)1 (2)8 (3)16 (4)18

24. J Deutsch 2003 23 Regents Question: 02/06 #6 Which element is classified as a noble gas at STP? (1)Hydrogen (2)Oxygen (3)Neon (4)Nitrogen STP is standard temperature and pressure 0ºC (273K) and 1 atm (101.3kPa)

25. J Deutsch 2003 24 The succession of elements within the same group demonstrates characteristic trends: differences in atomic radius, ionic radius, electronegativity, first ionization energy, metallic/nonmetallic properties. (3.1aa) Going down a group, there are more shells separating the nucleus from the valence electrons

26. J Deutsch 2003 25 The succession of elements across the same period demonstrates characteristic trends: differences in atomic radius, ionic radius, electronegativity, first ionization energy, metallic/nonmetallic properties. (3.1bb) Going across a period, there are more protons pulling on the valence electrons

27. J Deutsch 2003 26 Reference Table S

28. J Deutsch 2003 27 Trends in Atomic Radius  Atomic Radius – half the distance between two nuclei  Going down a group, the atomic radius increases because there are more principal energy levels (shells)  Going across a period, the atomic radius decreases because there are more protons pulling the valence shell closer

29. J Deutsch 2003 28 Atomic Radius

30. J Deutsch 2003 29 Regents Question: 06/03 #38 Which list of elements is arranged in order of increasing atomic radii? (1)Li, Be, B, C (2) Sr, Ca, Mg, Be (3) Sc, Ti, V, Cr (4) F, Cl, Br, I Check Table S

31. J Deutsch 2003 30 Forming Ions – making atoms happy  Atoms gain or lose electrons to complete their outer shell –A noble gas configuration –A complete octet –8 electrons  Metals lose electrons to form positive (+) ions  Nonmetals gain electrons to form negative (-) ions  Ionic Radius –A negative ion is always larger than its original atom. –A positive ion is always smaller than its original atom.

32. J Deutsch 2003 31 Regents Question: 06/03 #37 What is the total number of electrons in a Cu + ion? (1) 28 (2) 29 (3) 30 (4) 36

33. J Deutsch 2003 32 Ionic Radius in Metals  Sodium (Na) is a metal –Electron configuration 2-8-1 (11 protons and 11 electrons) –Loses 1 electron in its valence shell –A sodium atom becomes a sodium ion Na + 2-8 (10 electrons but 11 protons) –Same electron configuration as a noble gas (Ne) but has more protons. Electrons are pulled in much closer so the radius decreases.  2+ ions are even smaller than + ions

34. J Deutsch 2003 33 Ionic Radius in Nonmetals  Chlorine (Cl) is a nonmetal –Electron configuration 2-8-7 (17 protons and 17 electrons) –Gains 1 electron in its valence shell –A chlorine atom becomes a chloride ion Cl - 2-8-8 (18 electrons but only 17 protons) –Same electron configuration as a noble gas (Ar) but has fewer protons. Electrons repel each other and the radius increases.  2- ions are even larger than – ions Notice-name of negative ions end in IDE

35. J Deutsch 2003 34 Regents Question: 06/03 #60 As a neutral sulfur atom gains two electrons, what happens to the radius of the atom? It gets bigger

36. J Deutsch 2003 35 Regents Question: 06/03 #61 After a neutral sulfur atom gains two electrons, what is the resulting charge of the ion? 2-

37. J Deutsch 2003 36 Regents Question: 08/02 #23 Which electron configuration is correct for a sodium ion? (1) 2–7 (2) 2–8 (3) 2–8–1 (4) 2–8–2

38. J Deutsch 2003 37 Regents Question: 08/02 #47 Which ion has the same electron configuration as an atom of He? (1) H – (2) O 2– (3) Na + (4) Ca 2+ - means gains 1 electron 2- means gains 2 electrons + means loses 1 electron 2+ means loses 2 electrons GIN LIP Gaining electrons makes Ions Negative Losing electrons makes Ions Positive

39. J Deutsch 2003 38 Regents Question: 06/02 #39 Which of the following ions has the smallest radius? (1)F - (2)Cl - (3)K + (4)Ca 2+

40. J Deutsch 2003 39 Regents Question: 06/02 #30 As an atom becomes an ion, its mass number (1)Decreases (2)Increases (3)Remains the sam

41. J Deutsch 2003 40 Regents Question: 06/02 #10 Compared to the radius of a chlorine atom, the radius of a chloride ion is (1)Larger because chlorine loses an electron (2)Larger because chlorine gains an electron (3)Smaller because chlorine loses an electron (4)Smaller because chlorine gains an electron

42. J Deutsch 2003 41 Trends in Electronegativity  Electronegativity – the relative ability of an atom to attract electrons (in a chemical bond)  Fluorine (F) has the highest electronegativity and is assigned the value 4.0  Francium (Fr) has the lowest electronegativity.  Going down a group, electronegativity decreases because there are more shells and the electron being attracted is far from the protons  Going across a period, electronegativity increases because there are more protons in the nucleus to attract the electrons. (same number of shells)

43. J Deutsch 2003 42 Regents Question: 06/02 #11 Which of the following atoms has the greatest tendency to attract electrons? (1)Barium (2)Beryllium (3)Boron (4)Bromine

44. J Deutsch 2003 43 Regents Question: 01/03 #10 The strength of an atom’s attraction for the electrons in a chemical bond is the atom’s (1)Electronegativity (2)Ionization energy (3)Heat of reaction (4)Heat of formation

45. J Deutsch 2003 44 Trends in First Ionization Energy  First ionization energy is the amount of energy needed to remove the most loosely held electron from an atom in the gaseous state.  Going down a group, first ionization energy decreases because there are more shells and the electron being attracted is far from the protons  Going across a period, first ionization energy increases because there are more protons in the nucleus to attract the electrons. (same number of shells)

46. J Deutsch 2003 45 Regents Question: 01/03 #7 From which of these atoms in the ground state can a valence electron be removed using the least amount of energy? (1)Nitrogen (2)Carbon (3)Oxygen (4)Chlorine

47. J Deutsch 2003 46 Trends in Metallic Properties  Metals want to lose electrons to complete their outer shells  Metals form positive (+) ions  Metals have low electronegativity  Metals have low first ionization energy  Metallic properties (characteristics) decrease as you go to the right across a period  Metallic properties increase as you go down a group  Going towards Francium (Fr), metallic properties increases. Anything that increases an atom’s ability to lose electrons, increase the atoms metallic characteristics.

48. J Deutsch 2003 47 Trends in Nonmetallic Properties  Nonmetals want to gain electrons to complete their outer shells  Nonmetals form negative (-) ions  Nonmetals have high electronegativity  Nonmetals have high first ionization energy  Nonmetallic properties (characteristics) increase as you go to the right across a period  Nonmetallic properties decrease as you go down a group  Going towards Fluorine (F), nonmetallic properties increases. Anything that increases an atom’s ability to gain electrons, increase the atoms nonmetallic characteristics.

49. J Deutsch 2003 48 Regents Question: 06/02 #32 Which of the following Group 15 elements has the greatest metallic character? (1)Nitrogen (2)Phosphorous (3)Antimony (4)Bismuth

50. J Deutsch 2003 49 Regents Question: 06/02 #5 Which are two properties of most nonmetals? (1)High ionization energy and poor electrical conductivity (2)High ionization energy and good electrical conductivity (3)Low ionization energy and poor electrical conductivity (4)Low ionization energy and good electrical conductivity

51. J Deutsch 2003 50 Regents Question: 06/02 #67-69 On the grid in your answer booklet, set up a scale for electronegativity on the y-axis. Plot the data by drawing the best-fit line. Using the graph, predict the electronegativity of nitrogen For these elements, state the trend in electronegativity in terms of atomic number. ElementAtomic NumberElectronegativity Beryllium41.6 Boron52 Carbon62.6 Fluorine94.0 Lithium31.0 Oxygen83.4

52. J Deutsch 2003 51 Regents Question: cont’d

53. J Deutsch 2003 52 Regents Question: cont’d 1 2 3 4

54. J Deutsch 2003 53 Regents Question: Cont’d On the grid in your answer booklet, set up a scale for electronegativity on the y-axis. Plot the data by drawing the best-fit line. Using the graph, predict the electronegativity of nitrogen For these elements, state the trend in electronegativity in terms of atomic number. As the atomic number increases, the electronegativity increases. 1 2 3 4 3.0