Group 7- Halogens Flashcards
Properties of halogens
-Have seven electrons in outer shell
-Exist as diatomic molecules, with weak, intermolecular forces
-Highly reactive and toxic
-Type of bonding between atoms is covalent
-Nonmetallic properties: brittle, dull, poor conductors
Trends down the group
-Melting and boiling points increase
-Density increases
-Colours get darker
- Bleaching affect decreases
-Reactivity decreases
Reactions with alkali metals
-Alkali metals react with halogens to produce metal halide (salts)
Example of an alkali metal reacting with a halogen
Lithium + chlorine —> lithium chloride
2Li (s) + Cl2 (g) —> 2LiCl(s)
What colour is fluorine at room temperature?
Yellow
What colour is fluorines vapour?
Yellow
What state is fluorine at room temperature?
Gas
What colour is chlorine at room temperature?
Green
What colour is chlorines vapour?
Green
What state is chlorine at room temperature?
Gas
What colour is bromine at room temperature?
Orange/brown
What colour is Bromines vapour?
Orange
What state is bromine at room temperature?
Liquid
What colour is iodine at room temperature?
Grey
What colour is iodines vapour?
Purple
What state is iodine in at room temperature?
Solid
What are the most reactive elements in group one and group 7 start with?
An F
what is the bleaching effect of fluorine?
very strong
what is the bleaching effect of chlorine?
strong
what is the bleaching effect of bromine?
weak
what is the bleaching effect of iodine?
very weak
how does the bleaching effect change as you go down group 7?
it decreases
how do the melting and boiling points change as you go down group 7?
they increase
what kind of elements are all the elements in group 7?
diatomic
