Halogen Reactions

Question 1

What colour and state is fluorine at under standard conditions?

Answer 1

Pale yellow gas

Question 2

What colour and state is chlorine at under standard conditions?

Answer 2

Green gas

Question 3

What colour and state is bromine at under standard conditions?

Answer 3

Red-brown liquid

Question 4

What colour and state is iodine at under standard conditions?

Answer 4

Grey solid

Question 5

What’s the equation for silver nitrate reacting with a halide in solution?

Answer 5

Ag^+(Aq) + X^-(aq) —-> AgX(s)

Question 6

What colour is AgCl precipitate?

Answer 6

White precipitate which dissolves in dilute NH3

Question 7

What colour is AgBr precipitate?

Answer 7

Cream precipitate which dissolves in conc. NH3

Question 8

What colour is AgI precipitate?

Answer 8

Yellow precipitate which is insoluble in conc. NH3

Question 9

What happens to reactivity down group 7?

Answer 9

Halogens become less reactive because atomic radii increase, so…
• outer electrons are further from the nucleus
•more shielding so less attraction to the nucleus

Question 10

KCl(aq) + Cl2(aq)

Answer 10

• aqueous solution ~ stays colourless, no reaction

* organic solution ~stays colourless, no reaction

Question 11

KCl(aq) + Br2(aq)

Answer 11

• aqueous solution ~ no reaction, stays yellow

* organic solution ~ no reaction, stays orange

Question 12

KCl(aq) + I2(aq)

Answer 12

• aqueous solution ~ no reaction, stays orange/brown

* organic solution ~ no reaction stays purple

Question 13

KBr(aq) + Cl2(aq)

Answer 13

• aqueous solution ~ turns yellow, Br2 displaces

* organic solution ~ turns orange, Br2 displaced

Question 14

KBr2(aq) + Br2(aq)

Answer 14

• aqueous solution ~ no reaction, stays yellow

* organic solution ~ no reaction, stays orange

Question 15

KBr2(aq) + I2(aq)

Answer 15

• aqueous solution ~ no reaction, stays orange/brown

* organic solution ~ no reaction stays purple

Question 16

KI(aq) + Cl2(aq)

Answer 16

• aqueous solution ~ turns orange/brown, I2 displaced

* organic solution ~ turns purple, I2 displaced

Question 17

KI(aq) + Br2(aq)

Answer 17

• aqueous solution ~ turns orange/brown, I2 displaced

* organic solution ~ turns purple, I2 displaced

Question 18

KI(aq) + I2(aq)

Answer 18

• aqueous solution ~ stays orange/brown, No reaction

* organic solution ~ stays purple, No reaction