The Current Periodic Table

1. The Current Periodic Table • There is a periodic repetition of their physical & chemical properties when elements are arranged by their atomic number……this is called The Modern Periodic Law.

2. Groups…Here’s Where the Periodic Table Gets Useful!! • Elements in the same group have similar chemical and physical properties!! • (Mendeleev did that on purpose.) • Why?? • They have the same number of valence electrons. • They will form the same kinds of ions.

3. METALS More than ¾ of the known elements are metals. Metals share similar properties: • Good conductors of heat & electricity • Luster • Malleable & ductile • High densities • High boiling points & melting points • Resists stretching & twisting • Solids at room temperature • Write metal, cation, donates e in the top left corner of your PTE

4. NONMETALS • No luster • Poor conductors • May be solid, liquid or gas • Low densities • Low melting & boiling points • Write nonmetal, anion, accepts e in the top right corner of your PTE

5. METALLOIDS • Also called semimetals • Have properties of both metals and nonmetals • Outline the large black line with a marker..the elements that touch these are the metalloids

6. Hydrogen • Hydrogen belongs to a family of its own. • Hydrogen is a diatomic, reactive gas. • Hydrogen was involved in the explosion of the Hindenberg. • Hydrogen is promising as an alternative fuel source for automobiles • Color it red

7. German airship (called a zeppelin- means rigid airship) • 804 feet long • In 1937 it caught fire killing 35 of the 97 people on board. • Travelling from Germany to US; caught fire as it was landing in NJ

11. Alkali Metals • 1st column on the periodic table (Group 1) not including hydrogen. • Low densities & melting points • React with oxygen & moisture in air • Most reactive metals, always combined with something else in nature, they are not found uncombined (like salt) • Soft enough to cut with a butter knife • Will react violently with water & are stored under oil or kerosene • Label +1 and s1 on top of Group 1A

12. Alkaline Earth Metals • Second column on the periodic table. (Group 2) • Reactive metals that are always combined with nonmetals in nature. • Several of these elements are important mineral nutrients (such as Mg and Ca • Harder than alkali metals • Less reactive than alkali metals, not stored under oil or kerosene • Label +2 and s2 on top of Group 2A

13. Transition Metals • Elements in groups 3B-12B • Less reactive harder metals • Includes metals used in jewelry and construction. • Metals used “as metal.” • Label d1-d10 on top of transitional metals

14. Boron Family • Elements in group 3A • Aluminum metal was once rare and expensive, not a “disposable metal.” • Label +3 and p1 on top of Group 3A

15. Carbon Family • Elements in group 4A • Contains elements important to life and computers. • Carbon is the basis for an entire branch of chemistry (Organic Chemistry). • Silicon and Germanium are important semiconductors. • Label +/-4 and p2 on top of Group 4A

16. Nitrogen Family • Elements in group 5A • Nitrogen makes up over ¾ of the atmosphere. • Nitrogen and phosphorus are both important in living things. • Most of the world’s nitrogen is not available to living things. • The red stuff on the tip of matches is phosphorus. • Label -3 and p3 on top of Group 5A

17. Oxygen Family • Elements in group 6A • Oxygen is necessary for respiration. • Many things that stink, contain sulfur (rotten eggs, garlic, skunks,etc. • Label -2 and p4 on top of Group 6A • )

18. Halogens • Elements in group 7A • Very reactive, volatile, diatomic, nonmetals • Always found combined with other element in nature . • Form salts when combined with Groups 1 or 2 metals • Used as disinfectants and to strengthen teeth. • Label -1 and p5 on top of Group 7A

19. The Noble Gases

20. The Noble Gases • Elements in group 8A • VERY unreactive, monatomic gases • Occur in atmosphere in very small amounts • Used in lighted “neon” signs • Used in blimps to fix the Hindenberg problem. • Have a full valence shell. • Label 0 and p6 on top of Group 8A • Make a dash and label s2 out from He (see example)

21. Lanthanide Series • The lanthanide family is comprised of fifteen elements starting with lanthanum (La) at atomic number 57 and finishing up with lutetium (Lu) at number 71. • You might find some of these elements in superconductors, glass production, or lasers. • Label f1-f14 on top of these rows • Place a 4 out to the left of the row

22. Actinide Series • The actinide family is comprised of fifteen elements that start with actinium (Ac) at atomic number 89 and finish up with lawrencium (Lr) at number 103. • You have probably heard of plutonium (Pu), since it was used in atomic bombs. • Uranium (U) is also well known for its radioactivity. • They aren't all used to blow up the world. Some of them help us out every day. You can find americium (Am) is some metal detectors. • Label a 5 out to the left of the row

23. Diatomics • 7 elements are so reactive they are NOT found alone in nature • They are found in pairs called diatomics • H2, N2,O2,F2,Cl2,Br2,I2 • The Magic “7” • Color them all red

24. Elements as Building Blocks • The periodic table is organized like a big grid. • The elements are placed in specific places because of the way they look and act.

25. Periods • Even though they skip some squares in between, all of the rows go left to right. • When you look at a periodic table, each of the rows is considered to be a different period (Get it? Like PERIODic table.). There are 7 periods or rows • In the periodic table, elements have something in common if they are in the same row. • All of the elements in a period have the same number of electron orbitals.

26. A pattern of repeating order is called periodicity. In the mid-1800s, Dmitri Mendeleev, a Russian chemist, noticed a repeating pattern of chemical properties in elements. • Mendeleev arranged the elements in order of increasing atomic mass, to form something that resembles the modern periodictable. He was even able to predict the properties of some of the then-unknown elements. Later, the elements were rearranged in order of increasing atomicnumber. • The periodic table enables chemists and chemistry students to: • Learn the properties of families of elements (instead of learning the properties of each element), thus saving a lot of time and effort. • Find the relationships among elements and figure out the formulas of many different compounds. • Examine the atomic numbers, massnumbers, and information about the number of valenceelectrons.

27. Groups (Columns)

28. Same group=same valence electrons • The elements in a group have the same number of electrons in their outer orbital or valence electrons. • Group One has 1 valence electron, • Group Two has 2 valence electrons • Group 3 has… • Group 4, 5, 6, 7, 8….

29. Let’s Look at it another way… Using Bohr Diagrams

30. Drawing Bohr Diagrams

31. Step One • Determine the # of protons, electrons and neutrons • P=9 • E=9 • N=10

32. Step two • Draw a circle around the number of p and n, representing the nucleus

33. Step 3 • Draw the correct number of shells • Remember, the shells are the same number as the period • F is in the 2nd period, so it has 2 shells

34. Step 4 • Dots are the electrons • 2 can go in the first • 8 can go in the 2nd

35. But how do you know that there are 2 in the 1st shell, and 7 in the 2nd?? 1 2

36. Let’s Practice Some • C • O • Li • Cl • Ca • Now, it is easier to see the valence electrons

37. Be B 4 p+ 5 n° 5 p+ 6 n° O Na 8 p+ 8 n° 11 p+ 12 n° 2e– 6e– 2e– 8e– 1e– Al 13 p+ 14 n°