Group 7 Halogens

Question 1

What the group 7 elements?

Answer 1

halogens:

Fluorine, chlorine, bromine, iodine, astatine

Group 7 downwards

Question 2

Why do group 7 elements have the same properties?

Answer 2

As they have 7 electrons in outer shells , this means that they have to gain 1 electron to be full, they all travel as diatomic molecules , as they share an electron in a covalent bond.( two non metals).

Question 3

What are properties of group 7 elements? Chlorine,bromine,iodine?

Answer 3

The melting and boiling points as you go down the group.

Chlorine - fairly reactive, poisonous green gas
Bromine - poisonous , red brown liquid, orange vapour at room temperature
Iodine - dark grey crystalline sold, purple vapour when heated.

Question 4

Why does the reactivity decrease going down group 7?

Answer 4

As it gets harder to attract the extra electron to fill the outer shell when it’s further away from nucleus .

Question 5

How metals react with the halogens?

Answer 5

They will react vigorously with metals to make salts called metal halides.

Question 6

How does hydrogen react with the halogens?

Answer 6

Reacts to from hydrogen halides , these are soluble and can be dissolved to make an acidic solution. Eg HCl forms hydrochloric acid in water .