Halogens

Question 1

At room temperature what colour is Fluorine

Answer 1

Yellow gas

Question 2

At Room temp what colour is Chlorine

Answer 2

Pale green

Question 3

At room temp what colour is Bromine

Answer 3

Brown LIQUID

Question 4

At room temp what colour is iodine

Answer 4

dark grey SOLID

Question 5

Why do boiling points of halogen increase down the group

Answer 5

Number of electrons in Halogen molecules increases so strength of van der waals forces of attraction between molecules increases

Question 6

What is an oxidising agent

Answer 6

A species that oxidises another substance by removing electrons from it

Question 7

Halogens are good…

Answer 7

oxidising agents

- they are reduced themselves during reaction

Question 8

What happens to oxidising ability down the group

Answer 8

decreases, the atomic radii increases and so does shielding meaning attraction between nucleus and electron decreases and oxidising ability decreases and it cannot gain electrons as easily

Question 9

What colour is Chlorine in water

Answer 9

pale green

Question 10

What colour is Bromine in water

Answer 10

orange

Question 11

what colour is iodine in water

Answer 11

brown

Question 12

What colour is chlorine in Cyclohexane

Answer 12

pale green

Question 13

Colour of bromine in cyclohexane

Answer 13

orange

Question 14

colour of iodine in cyclohexane

Answer 14

violet

Question 15

Halide ions are good…

Answer 15

reducing agents

Question 16

Trend in reducing ability of halide ion

Answer 16

the reducing ability increases down the group as the ion is lager and loses the electron more easily

Question 17

How can you identify Halide ions

Answer 17

acidified silver nitrate solution

Question 18

When you react fluoride with acidified silver nitrate solution what is observed

Answer 18

Fluoride ions from silver fluoride (AgF) no precipitate seen
soluble salt

Question 19

When you react Chloride with acidified silver nitrate solution what is observed

Answer 19

AgCl
White precipitate
insoluble

Question 20

When you react bromide with acidified silver nitrate solution what is observed

Answer 20

AgBr
cream precipitate
insoluble

Question 21

When you react iodide with acidified silver nitrate solution what is observed

Answer 21

AgI
Yellow
insoluble

Question 22

Other than colours of silver salt, what can confirm the identity of halide ions

Answer 22

Solubility of silver halides in ammonia

Question 23

What is the solubility of AgCl in ammonia

Answer 23

Dissolves in DILUTE ammonia solution

Question 24

Solubility of AgBr in ammonia

Answer 24

Does not dissolve in dilute ammonia solution

DOES dissolve in CONCENTRATED ammonia solution

Question 25

Solubility of AgI in ammonia

Answer 25

Doesn’t dissolve in dilute or conc ammonia solution

Question 26

What is a disproportionation reaction

Answer 26

simultaneously oxidised and reduced

Question 27

What is the Chlorine and water treatment equation

Answer 27

Cl2(aq) + H2O(l) <=> HClO(aq) + HCl(aq)

Question 28

Why is silver nitrate acidified

Answer 28

to remove ions that would interfere with test

prevent formation of silver precipitate compounds that would interfere with test

remove ions thats react with silver nitrate

Question 29

Why is Hcl not used to acidify silver nitrate solution for the test for halide ions

Answer 29

would form a white precipitate which would interfere with results of the test