The Periodic Table

We will start with a song! Element Song

Who was the first person to write down all the known elements? Antoine Lavoisier, in the 1700 ’ s

How many elements were there at the time? 33 Tony Dorsett

By 1870 how many known elements were there? About 70

Who arranged the first periodic table? John Newlands

How did he arrange the P.T.? By increasing atomic mass

What did Newlands notice? Their properties repeated every 8 th element.

Who gets the real credit for making the periodic table? Dmitri Mendeleev, in 1869

How did he arrange the periodic table? By atomic mass

What else did he look at? Chemical and physical properties

When he was placing all of the elements what did he do? Left 3 empty spaces

Why did he leave empty spaces? He predicted elements would be discovered to fill the spaces.

Why was this a big deal? Within a few years the elements were discovered, and had his predicted properties.

Who was the next scientist to work on the periodic table? Henry Moseley

What did Moseley do? Realized it should be by atomic number, not mass, and changed a few elements around.

What did this lead to? Periodic Law

What does the periodic law state? Elements arranged by number have similar properties in regular intervals.

How is the modern periodic table arranged? Just like Moseley ’ s periodic table, in rows and columns.

What is a horizontal row called? A period

What is a vertical column called? A family or group

How is the periodic table grouped? By metals, metalloids, and non-metals.

What is a metal? An element that is shiny, good conductor of heat and electricity, is ductile and is malleable.

What is a nonmetal? An element that is a poor conductor, dull, brittle and is not ductile or malleable.

What is a metalloid? It is an element that has properties of both metals and nonmetals.

How do you find them? Make the stair step. If it touches the line on a full side, it is a metalloid. Except Al and Po.

Do the families on the periodic table have names? Yes

Where are the alkali metals? Group 1

Is Hydrogen included? No, H is its own family Non-metal 1 valence electron

What are some characteristics of alkali metals? Do not exist in nature alone Highly reactive Soft metals 1 valence electron

Side note! Weird Element Name News Flash! Potassium (K) Comes from Latin for Kalium Sodium (Na) Comes from Latin Natrium

What are group 2 elements called? Alkaline Earth Metals

What are the characteristics of alkaline earth metals? Highly reactive Soft metals 2 valence electrons

What is a transition metal? Anything in groups Metals Varying numbers of valence electrons

What are the characteristics of transition metals? Conductors of heat and electricity, shiny, malleable, ductile

Side Note! Weird Element Names! Iron (Fe)- Latin for Ferrum Copper (Cu)- Latin for Cuprum Silver (Ag)- Latin for Argentum Tungsten (W)- German for Wolfram Gold (Au)- Latin for Aurum Mercury (Hg)- Latin for Hydrargyrum, mercury the planet closest to gold (the sun)

What are the lanthanides and actinides? The f-block elements Most are Radioactive Metals

What is a halogen? An element in group 17.

What are the characteristics of halogens? Highly reactive elements Non-metals 7 Valence electrons

What is group 18 called? The noble gases.

What are the characteristics of noble gases? Non-reactive, all gases, always single elements Full Valence Shells Non metals

What is a valence electron? The electrons on the outermost energy level.

How do I find the number of valence electrons? Use the group! 1 has 1 2 has 2 13 has 3 14 has 4 15 has 5 16 has 6 17 has 7 18 has 8 (He only has 2)

What is another way the PT can be divided out? Representative elements, transition metals, and inner transition metals.

What are representative elements? Elements in the s and p block

What are transition metals? The d block

What are inner transition metals? The f block

What is a periodic trend? Predictable properties of elements based on the periodic table.

What family will be left out of the periodic trends? The noble gases, except for atomic radius.

Why is that? They are happy with full valence shells.

If an atom wants to lose an electron what do they look like? They are big

If an atom wants to keep its electrons what does it look like? It is small

What is atomic radius? How big one atom of the element is.

What is the atomic radius trend? Going across a period atoms get smaller Going down a group they get larger.

What is ionization energy? The amount of energy needed to remove an electron from an atom.

Why would an atom want to remove electrons? To have full valence shells.

What is the periodic trend? As you move across a period it increases As you move down a group it decreases.

What is electronegativity? The ability for an atom to attract electrons.

What is the periodic trend for electronegativity? Increases across a period Decreases down a group

What is an ion? An atom that has gained or lost an electron.

What is a cation? A positive ion (atom that loses electrons)

What is an anion? A negative ion. (atom that gains electrons)

Try It! Find the number of p +, n o, and e - for: Sr +2 As -3

What is an oxidation number? The charge on the ion. It tells the number of electrons lost or gained. Could be positive or negative

How can I use the PT to figure out oxidation numbers? By group number: Group 1 = +1 Group 2 = +2 Group 13 = +3 Group 14 = +4 or -4 Group 15 = -3 Group 16 = -2 Group 17 = -1

What about groups 3-12? They lose different numbers of electrons, but all lose electrons.

How do I know how many electrons groups 3-12 lose? It will be given to you, but most are +1 or +2

What happens when atoms lose electrons? It is striving to look like a noble gas. When it has an octet, it shrinks.

What is an octet? A full shell, 8 valence electrons.

What is ionic radius? How big the ion is.

What happens once an atom has a full valence shell? As an ion, they shrink to be as small as possible.