THE PERIODIC TABLE dayah/periodic/Images/periodic table.png

1. THE PERIODIC TABLEhttp://www.dayah.com/periodic/Images/periodic table.png • Mendeleev’s Periodic Table (Figure 6.3) • Arranged elements into rows and columns • Elements ordered by atomic mass.

2. THE PERIODIC TABLE • Modern periodic tables (Figure 6.5) • Also arrange elements into rows and columns. • Elements are ordered by increasing atomic number

3. PERIODIC LAW • There are 7 periods (rows) in the periodic table. • Period 1 = 2 elements • Period 2 = 8 elements • Period 3 = 8 elements • Period 4 = 18 elements • Period 5 =18 elements • Period 6 = 32 elements • Period 7 = 24 elements • Each period = principal energy level.

5. PERIODIC LAW • Elements within a Group (column) have similar properties. • The properties of elements within a period change as you move across a period from left to right. • PERIODIC LAW STATES: when elements are arranged in order of increasing atomic number, there is a periodic repetition of their physical and chemical properties.

6. Metals, Nonmetals, Metalloids • Metals • 80% of elements • Good conductors of heat and electric current • All are solids at room temperature (EXCEPT: mercury!) • Ductile (drawn into wires) • Most are malleable

7. Metals, Nonmetals, Metalloids • Nonmetals • Found in the upper right hand corner of the periodic table • Most are gases at room temperature (i.e. oxygen and nitrogen) • Poor conductors of heat and electric current (except carbon) • Solid nonmetals tend to be brittle

8. Metals, Nonmetals, Metalloids • Metalloids • Properties similar to both metals and nonmetals • Depending on the conditions a metalloid may behave like a metal or a non metal.

9. Checkpoint • Which of these sets of elements have similar physical and chemical properties? • a. oxygen, nitrogen, carbon, boron • b. strontium, magnesium, calcium, beryllium • c. nitrogen, neon, nickel, niobium • Identify each element as a metal, metalloid, or nonmetal. • a. gold metal c. sulfur non metal • b. silicon metalloid d.barium metal

10. Classifying Elements • For helium, label the element symbol, element name, atomic number and the atomic mass. • Label all groups and periods • Color code (entire box) with key • Metals • Non metals • Metalloids • Gas • Liquid • Solid • Indicate where to find: • Alkali metals, alkaline earth metals, halogens, noble gases • *** Put your name and date at the top!

11. The Representative Elements • Groups IA through 7A. • The valence electrons (electrons in the highest occupied energy level)= group number!

12. Transitional Elements • Columns 3-12 (or Groups IB-VIIIB) • Transition metals and inner transition metals • Transition metals have e- in d orbitals (main body) • Inner transition metals have e- in f orbitals (formerly known as rare earth metals)

13. Practice Problems • Use figure 6.9 and Figure 6.12 (or the s,p,d,f handout) to write the electron configurations of the following elements. • A. Carbon • 1s2 2s2 2p2 • B. Strontium • 1s2 2s2 2p63s23p63d104s24p65s2 • C. Vanadium • 1s2 2s2 2p63s23p63d34s2

15. PERIODIC TRENDS • Atomic Radius • 1/2 the distance between the nuclei of two atoms of the same element when the atoms are joined. • Measured in picometers(pm) • there are one trillion (1012 pm in one meter) • Decreases because # of protons increases therefore attractive forces are pulling in the e-’s . • Increases because you are adding more energy levels.

16. IONS • Ions-charged atoms due to the gain/loss of electrons • Anion- ion with a negative (-) charge (nonmetals) • Cation-ion with a positive (+) charge (metals) • When compounds form, elements gain or lose e-’s to form ions in order to attain a stable noble gas configuration.

17. Ionization Energy • Ionization Energy (IE) • The amount of energy needed or absorbed to remove an electron from an atom. • The further away an e- the less IE needed to remove the e-.( but also consider protons and electrons are increasing)

18. IONIC SIZE • Anions (-) are larger than cations (+) due to taking e-’s away which reduces the radius. • Among the anions and cations the trend is the same as atomic radius • Decreases  • Increases 

19. ELECTRONEGATIVITY • Electronegativity (EN) • The ability of an atom to attract itself the electrons when in a compound (bonded). • Electrons shift toward the more EN atom

20. PERIODIC TREND SUMMARY

21. PRACTICE • Atomic Radius--rank the following according to size from smallest to larger. • Mg, Al, Ca • Al < Mg < Ca • S, Cl, S-2 • Cl < S < S-2 • Fe +2, Fe, Fe +3 • Fe +3 < Fe +2 < Fe

23. PRACTICE • Which element in each pair has a higher electronegativity value? • Cl or F • F • C or N • N • Mg or Ne • Mg • As or Ca • As