Halogens Flashcards
What is observed when chlorine or bromine reacts with iron?
A violent reaction, orange glow, light and heat produced
What is observed when iodine reacts with iron?
No visible reaction
What is the product of the reaction between a halogen and a metal?
A metal halide
Description of fluorine at r.t.p
Pale yellow gas
Description of chlorine at r.t.p
Pale yellow/green gas
Description of bromine at r.t.p
Brown liquid
Two descriptions of iodine
Grey and soft solid at room temperature.
Purple when in vapour form
What is a use of fluorine?
Fluoride in toothpaste to prevent tooth decay
What is chlorine used for?
To kill bacteria in swimming pools, to whiten paper , salt added to food
What is bromine used for?
Silver bromide in photographic film
Used in medicines
What is iodine used for?
As an antiseptic
What happens to the reactivity of halogens as you move down the group?
It decreases
Why is fluorine more reactive than chlorine?
Fluorine has fewer electron shells. The outer shell is closer to the positive nucleus. It is easier to attract an electron during a reaction
What happens to density as you move down the group?
It increases
What happens to melting and boiling points as you move down the group?
They increase
