Catherine, Melissa, Jennifer

The Halogens are fluorine, chlorine, bromine, iodine, and astatine.

Halogen is derived from a Greek word meaning “salt-producing”

Group 17 in the table. These certain elements are highly reactive oxidizers.

They all are missing 1 charge in their outer charge so they combine with many elements to form ions.

All have strong unpleasant odor and will burn flesh. Does not dissolve well in water.

Highly toxic and can cause severe burns on contact

Used for etching glass Also used as a catalyst

to speed up chemical reactions

Used as a weapon in WWII

Used in toothpaste to strengthen

It is a pale green gas of low density

Atomic #:9, atomic mass: 18.998403 amu

#of protons/electrons: 9 # of neutrons: 10 Crystal structure: cubic # of energy levels:2 1st level- 2, 2nd level: 7 Date of discovery-

1886, Joseph Henn Moissan

Used as a bleaching agent

Used as a disinfectant in swimming pools

Used as a weapon in WWI

Atomic #:17, atomic mass: 35.4527 amu

# of protons/electrons: 17

# of neutrons: 18 Crystal structure:

orthorhombic

Color: green In room temp form it

is a gas # of energy levels: 3 1st- 2, 2nd- 8, 3rd- 7 Date of discovery-

1774, Carl Wilhelm Scheele.

Uses: water purification, bleaches

Foul smelling reddish-brown liquid

Used in dyes Used in applications

such as pesticides, disinfectants, medicines, and flame retardants

Was once used for an additive for gasoline containing lead.

Atomic #: 35, atomic mass:79.904 amu

#ofprotons/electrons:35 # of neutrons: 45 # of energy levels: 4,

1st- 2, 2nd- 8, 3rd- 18, 4th- 7

Date of discovery- 1826, Antoine J Balar

Uses- poisonous In room temp. form is a

liquid

Iodine is important in the human diet

The thyroid gland produces a growth-regulating hormone that contains iodine, and lack of iodine can cause a goiter, a swelling around the neck

Was once used in the development of photography

Atomic #:53, atomic mass: 126.9044 amu

#of protons/electrons: 53 # of neutrons: 74

It’s a solid # of energy levels-5

1st- 2, 2nd- 8, 3rd- 18, 4th-18, 5th- 7

Date of discovery- 1811, Bernard Courtois

Uses: required in humans

Unstable, it is difficult to say what applications it may have. Also not found in nature.

The most promising area involves the use of astatine to treat a condition known as hyperthyroidism, related to an overly active thyroid gland

Atomic #: 85, atomic mass: 210.0 amu

#of protons/electrons: 85, # of neutrons: 125

Energy levels: 6, 1st- 2, 2nd- 8, 3rd- 18, 4th- 32, 5th- 18, 6th- 7

Date of dicovery- 1940, D.R. Corson

No uses known Is a solid in room

temp.

http://www.scienceclarified.com/everyday/Real-Life-Chemistry-Vol-2/Halogens.html

www.theodoregray.com/periodictable http://www.chem4kids.com/files/

elem_families.html http://www.chemtutor.com/perich.htm http://www.learner.org/interactives/

periodic/groups.html