Group 7 - Halogens Flashcards
How many electrons do the halogens have in their outer shell?
7 electrons
What do the halogens exist as?
Diatomic molecules
What do the halogens have to do to have a full outer shell?
Share covalently
As you go down Group 7, what happens to the melting and boiling points of the halogens?
Increase
What is chlorine at room temperature?
Chlorine is fairly reactive, poisonous green gas.
What is the state of bromine at room temperature?
A poisonous, red-brown liquid, which gives off an orange vapour.
What is iodine at room temperature?
A poisonous, dark-grey crystalline solid which gives off a purple vapour when heated.
What could you predict astatine to be at room temperature and why?
A dark-coloured solid because the melting points increase down the group and the colour gets darker.
What is the test for chlorine?
It bleaches damp litmus paper, turning it from blue to white (it might turn red for a moment first through because a solution of chlorine is acidic.
As you go down the group, what happens to the reactivity of the halogens ?
Decreases
The easier it is for a halogen to attract an electron…
…the more reactive it will be.
What do the halogens react with to form?
Metal halides
What is the equation for halogen reacting with a metal?
H2 + 2M ——> 2MH
What do a hydrogen and halogen react to form?
Hydrogen halide.
What is the equation for a hydrogen halide?
Ha2 + H2 ——> 2HHa
