Matt Battipaglia and Pooja Patel
The Periodic Table
Period 3

Matt Battipaglia and Pooja Patel
The Periodic Table
Period 3
Periodic Relationships among the Elements Midterm Review Sheet
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A = Mass Number (# of protons + # of neutrons)
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Z = Atomic Number (# of protons in nucleus)
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X = Element Symbol (letter(s) representing an element)
Isotopes = Atoms of the same element that have different number of neutrons and thus different atomic masses
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Molecule = Two or more atoms chemically bonded together in a definite arrangement o
Diatomic Molecule = Molecule that only contains 2 atoms o
Polyatomic Molecule = Molecule that has more than 2 atoms
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Ion = An atom or group of atoms that have a net positive or negative charge o
Cation = Ion with positive charge; neutral atom loses electrons to become a cation o
Anion = Ion with negative charge; neutral atom gains electrons to become an anion o
Monatomic Ion = ion which contains only one atom o
Polyatomic Ion = ion which contains more than one atom
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Dimitri Mendeleev = Developed the first periodic table o
Arranged elements by increasing atomic mass in 1781 o
Elements with similar properties organized in the same column o
Predicting properties of elements not yet discovered in his time and left room for them on table
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H.G. Moseley = Arranged elements in same manner as modern periodic table o
Arranged elements by atomic number
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Valence Electrons = Electrons in the outermost energy level of an atom; electrons available to be lost, gained, or shared in the formation of chemical compounds; cause reactions to occur; elements have similar properties if they have the same amount of valence electrons
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Inner Core Electrons: Electrons under the highest energy level
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Isoelectronic: Ions that have the same electron configuration
Periodic Law: When elements are arranged in order of increasing atomic number, their physical and chemical properties show a periodic (repeating) pattern.
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Patterns on the periodic table are called periodic trends
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Atomic Radius: Half the distance from center-center of 2 like atoms
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Ionic Radii: Half the distance from center-center of 2 like ions
Ionization Energy: Minimum energy (kJ/mol) required to remove an electron from a gaseous atom in its ground state
Electronegativity: Tendency for an atom to attract electrons
Electron Affinity: The negative of the energy change that occurs when an electron is accepted by an atom in the gaseous state to form an anion.

Matt Battipaglia and Pooja Patel
The Periodic Table
REVIEW QUESTIONS
1. The most electronegative element is _____
2. The element which forms compounds with almost all elements is_______
3. Which among the following is the biggest in size?
Rb +
Rb -
Rb
4. Fill in the blanks. a) The smallest atom in group 8A is ___ b) The largest atom in group 6A is ____
5. Isoelectronic ions have _____ electronic configuration.
6. Which group has elements with 7 valence electrons? _____
7. Find the noble gas configurations of the following: a) Mg 2+ b) As 3c) Pd d) Ir 2+ e) Ta + f) Br g) Cs +
8. Which of the following elements have similar chemical properties? (pick all that apply)
Period 3 a) Ru b) Fe c) Cu 3+ d) Zr e) W 2f) Ir 2+
9. Arrange the following in order of decreasing atomic radius. a) Fe 3+ b) Co 4+ c) Ni
10. Arrange the following in order of increasing ionic radius. a) Ag b) Co c) Rh
11. Arrange the following in order of increasing ionization energy. a) Pb b) O c) Hg
12. Arrange the following in order of decreasing electronegativity. a) Cl b) At c) Tl
13. Arrange the following in order of increasing electron affinity. a) Ru b) Rb c) Ra
14. What is the most reactive metal? ___________
15. What are representative elements? __________

Matt Battipaglia and Pooja Patel
Answer key
1. Fluorine
2. Fluorine
3. Rb -
4. a) He b) Po
5. same
6. Group 7A (halogens)
7. a) [Ne] b) [Kr] c) [Kr] 4d8 5s2 d) [Xe] 4f14 5d7 e) [Xe] 4f14 5d3 6s1 f) [Kr] g) [Xe]
8. Fe, Cu 3+ , W 2-
9. Ni, Fe 3+ , Co 4+
10. Co, Ag, Rh
11. Hg, Pb, O
12. Cl, At, Tl
13. Ra, Rb, Ru
14. Francium
15. Elements in groups 1, 2, 13-17; also called main group elements
Picture Version of Periodic Table (in case of formatting issues):
The Periodic Table
Period 3