Group 7 Flashcards
What is the name for group 7 elements?
Halogens
Halogens exsist as pairs of atoms that we call…?
Diatomic molecules
How many electrons do halogens have in their outer shell?
7
What happens to the boiling and melting points of halogens as you go down the group?
They increase
What happens to the reactivity of halogens as you go down the group
It decreases
Why does the reactivity of halogens decrease as you go down the group
As you go down, the atomic radius increases, so the outermost shell becomes further away from the positive nucleus.
And the outerelectrons are shieded from the positive nucleusby the internal electrons. This weakens the force of attraction between the outer electrons and the nucleus, so it becomes more difficult to attract another electron into the outer energy shell
What happens when a halogen reacts with a metal and gains an electron?
It becomes a negatively charged halide (ion)
More reactive halogens will always ——- less reactive ones
Fill the blank
Displace
What happens when a halogen reatcs with hydrogen
It becomes an acidic hydrogen halide
What is formed when a halogen bonds with a non-metal
A covalent compound
Why does the boilingand melting pioint of ahalogen increase as you go down the group?
The atoms gain more outer electron shells and the intermolecular forces become stronger. Therefore, a greater amount of energy is required to break the forces, so they have a high melting and boiling point
What happens to the colour of halogens as you go down the group
It becomes darker
Describe the trend in state of matter as you go down group 7
Gas - Flourine + Chlorine
Liquid - Bromine
Solid - Iodine + Astatine
This is due to the increasing of melting and boiling points as you go down the group
A more reactive halogen can —– a less reactive halogen from an aqeuous solution of its salt
