The Halogen Family

The Halogens

• The halogens are a group of non- metals in the periodic table

• They all have seven electrons in their outer shell this makes them all really reactive; they only have to gain one more electron to fill their outer shell.

• Unlike Group One the elements get less reactive as you go down the group.

Fluorine 2,7

Name: Fluorine Symbol: F Atomic Number: 9 Atomic Mass: 18.998404 amu Melting Point: -219.62 °C

Boiling Point: -188.14 °C Number of Protons/Electrons: 9 Number of Neutrons: 10 Colour: Greenish

Chlorine 2,8,7

Name: Chlorine Symbol: Cl Atomic Number: 17 Atomic Mass: 35.4527 amu Melting Point: -100.98 °C

Boiling Point: -34.6 °C

Number of Protons/Electrons: 17 Number of Neutrons: 18

Colour: green

Bromine 2,8,18,7

Name: Bromine Symbol: Br Atomic Number: 35 Atomic Mass: 79.904 amu Melting Point: -7.2 °C

Boiling Point: 58.78 °C

Number of Protons/Electrons: 35 Number of Neutrons: 45

Colour: Red

Iodine 2,8,18,18,7

Name: Iodine Symbol: I Atomic Number: 53 Atomic Mass: 126.90447 amu Melting Point: 113.5 °C

Boiling Point: 184.0 °C

Number of Protons/Electrons: 53 Number of Neutrons: 74

Colour: blackish

Astatine 2,8,18,32,18,7

Name: Astatine Symbol: At Atomic Number: 85 Atomic Mass: (210.0) amu Melting Point: 302.0 °C

Boiling Point: 337.0 °C

Number of Protons/Electrons: 85 Number of Neutrons: 125 Colour: Unknown

Uses of Fluorine

The main use of fluorine is toothpaste even though it isn’t as fluorine itself but instead as fluoride, a compound of fluorine.

Uses of Chlorine

Chlorine is used mostly to kill bacteria or as a bleach. Chlorine bleaches a piece of universal indicator paper white.

Uses of Bromine

Bromine is one of the main ingredients in camera films (as silver bromide).

Uses of Iodine

When dissolved in water, iodine can be used as a strong antiseptic or as a test for starch.

Group 17—The Halogen Group

• All the elements in Group 17 are nonmetals except for astatine, which is a radioactive metalloid.

Representative ElementsRepresentative Elements

• These elements are called halogens, which means “salt-former.”

• All of the halogens form salts with sodium and with the other alkali metals.

Group 17—The Halogen GroupRepresentative ElementsRepresentative Elements

• Chlorine is less reactive than fluorine, and bromine is less reactive than chlorine.

• Iodine is the least reactive of the four nonmetals.

Displacement reactionsTo put it simply, a MORE reactive halogen will displace a LESS reactive halogen from a solution of its salt.

F

Cl

Br

I

Decre

asin

g re

activ

ity

Potassium chloride KCl(aq)

Potassium bromide

KBr(aq)

Potassium iodide KI (aq)

Chlorine Cl2

Bromine Br2

Iodine I2

Properties of the Halogens

F

Cl

Br

I

At

Colour

Green

Orange

Grey/black

State

Gas

Liquid

Solid

Yellow

Black

Solid

Gas

INC

RE

AS

ING

M

OL

EC

UL

AR

SIZ

E

INC

RE

AS

ING

DE

NS

ITY

DE

CR

EA

SIN

G

RE

AC

TIV

ITY

Uses of the Halogens

Fluorine

IodineBromine

ChlorineToothpaste

Water treatment

Extraction of Aluminium

Non stick coatings

Enrichment of Uranium

Water disinfection

Hydrochloric acid

Plastics

Bleaches

Photographic film

Tear gas

Flame retardants

Pharmaceuticals

Disinfectant

Halogen lamps

X ray diagnosis

Salt additive

Thyroid treatment

Cancer treatment

Reactions of the Halogens (1)

All of the halogens will react with Alkali metals to produce ionic compounds

ALKALI METAL + HALOGEN METAL HALIDE

Sodium + Chlorine Sodium Chloride

2Na + Cl2 2NaCl

Complete these equations

Lithium + Bromine

Potassium + Iodine

Lithium Bromide

Potassium Iodide

Reactions of the Halogens (2)

All of the halogens will react with Hydrogen to produce gasas

HYDROGEN + HALOGEN HYDROGEN HALIDE

Hydrogen + Chlorine Hydrogen Chloride

H2 + Cl2 2HCl

Complete these equations

Hydrogen + Bromine

Hydrogen + Iodine

Hydrogen

Bromide

Hydrogen IodideFollow the pattern to write the balanced chemical equations

Reactions of the Halogens (3)

All of the halogens will react with water to produce 2 acids

WATER + HALOGEN ACID 1 + ACID 2

Water + Chlorine Hydrochloric + Hydrochlorus

Acid Acid

H2O + Cl2 HCl + HOCl

This also happens with Bromine and Iodine and the acids

formed are much stronger!

Thank you

Ashish KumarPowered by: