Group 7 elements

Question 1

What is the colour and physical state of Chlorine at room temperature?

Answer 1

Green, gas

Question 2

What is the colour and physical state of Bromine at room temperature?

Answer 2

Red-brown, liquid

Question 3

What is the colour and physical state of Iodine at room temperature?

Answer 3

Dark grey, solid

Question 4

Describe the trends in chemical and physical properties of the halogens?

Answer 4

As you go down the group, the elements have a darker colour, a higher bpt, and are less reactive

Question 5

Describe the dissociation of HCl gas into HCl acid?

Answer 5

Hydrogen chloride has the formula HCl and is a gas at room temperature. When it is dissolved in water the molecules split up into H+ ions and Cl- ions, this is called dissociation. The solution formed is hydrochloric acid and is acidic because it contains H+ ions

Question 6

Why is hydrogen chloride acidic in water but not in Methylbenzene?

Answer 6

If HCl is dissolved in an organic solution, then it doesn’t dissociate into H+ and Cl- ions. This means there are no H+ ions so it’s not acidic

Question 7

What happens if you react halogens together?

Answer 7

More reactive halogens will displace less reactive ones

Question 8

Give an example of a displacement reaction involving halogens?

Answer 8

If you add chlorine water to potassium iodide, the chlorine will react with the potassium to form potassium chloride. The iodine is displaced