1. Catherine, Melissa, Jennifer
Halogens
Catherine, Melissa, Jennifer

2. Halogen in Everyday Life
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.

3. Fluorine- most reactive
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: 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

4. Chlorine Used as a bleaching agent
Used as a disinfectant in swimming pools
Used as a weapon in WWI
Atomic #:17, atomic mass: 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

5. Bromine 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
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.

6. Iodine 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: 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

7. Astatine- the rarest
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: 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.

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