Groups in the Periodic Table

http://www.edu-cyberpg.com/IEC/elementsong.html

Another element song: http://www.youtube.com/watch?v=d0zION8xjbM&feature=related

The set of elements in the same column in the periodic table is a chemical group.

These elements have similar physical and chemical properties. They form similar compounds when they combine with other elements. Their behaviour can be explained using Bohr-Rutherford diagrams. The key feature is the elements in a group have the same number of electrons in their outermost shell. These electrons are called VALENCE electrons.

A vertical column of elements in the periodic table is called a Chemical Group.

A horizontal row of elements in the periodic table is called a Period.

 

Alkali Metals – Group #1/1AOuter orbit has only one electronLithium (Li), Sodium(Na), Potassium (K),

Rubidium (Rb), Cesium (Cs), Francium (Fr)Shiny, silvery-grey, softer than most

other metals, malleable, ductile, conduct electricity and heat

Very reactive – combine with other elements easily, reacts vigorously with water to make H2 gas

Found in nature only as compounds

Alkali metals can explode if they are exposed to water.

Let’ See some Alkali metals!Li - demoNa - demoK –demoWhat do you notice about the reaction of these?

RbCsFr

Videos of Li to Cs

Brainiac Version (3:17): http://www.youtube.com/watch?v=eCk0lYB_8c0&feature=related

Another Version(2:22): http://www.youtube.com/watch?v=uixxJtJPVXk

Why no Fr?(3:07): http://www.youtube.com/watch?v=PyFLvSg6ZDw

Alkaline Earth Metals – Group #2/2AOuter orbit has 2 electronsBeryllium (Be), Magnesium (Mg), Calcium

(Ca), Strontium (Sr), Barium (Ba), Radium (Ra)

Shiny metals

Reactive

Form compounds that are often insoluble in water.

Because of their reactivity, not found free in nature.

Halogens – Group #17/7A

Outer orbit has 7 electrons.Fluorine (F), Chlorine (Cl), Bromine (Br),

Iodine (I), Astatine (At)

Non-metals, each has noticeable colour

Very Reactive, very corrosive

Found in nature as compounds

Term "halogen" means "salt-former" and compounds containing halogens are called "salts“

Halogen song (3 min): http://www.youtube.com/watch?v=Qvs4NTB71uY&NR=1Comparing 4 halogens (4 min): http://www.youtube.com/watch?v=u2ogMUDBaf4&feature=related

Noble Gases – Group #18/8AOuter orbit of electrons is full

with 8, making them stable.Helium (He), Neon (Ne), Argon (Ar),

Krypton (Kr), Xenon (Xe), Radon (Rn)

Gases at room temperatureOdourless, colourless, tasteless

Very stable and inert – they rarely form compounds

If an electric current is passed through each gas, each will glow brightly (ex. Neon signs)Discharge Tube Demo

Comparing 5 noble gases(1:17 min): http://www.youtube.com/watch?v=QLrofyj6a2s&feature=related

Mythbusters Why He changes voice (0.39 min): http://www.youtube.com/watch?v=d-XbjFn3aqE&NR=1

Hydrogen (H) (Group of one)

Unique.

One electron in its outer orbit – reactive.

Colourless, odourless, tasteless gasVery reactive - highly flammable

When reacting: sometimes it loses its electron, sometimes it gains an electron

Unstable electronic structureMain element in living things, oil,

coal, natural gasH Balloon Demo

Hindenburg: http://www.youtube.com/watch?v=H47x9q5-C2k&feature=player_embedded#!

MetalloidsNot really a group by

themselves.Boron (B), Silicon (Si), Germanium

(Ge), Arsenic (As), etc… Found on the right hand side of

the periodic table on either side of the zig-zagzig-zag line separating metals and non-metals.

Have both metallic and non-metallic properties.

Some of the metalloids, such as silicon and germanium, are semi-conductors

Home Fun :

1) Read pages 178-183.

a) Define alloy and provide an example.

b) Answer #1-5 on page 183

2) Read pages 193-195

a) Answer #1, 2 on page 195