3: Group 7 Flashcards

1
Q

What colour is flourine?

A

Yellow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What colour is chlorine?

A

Green

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What colour is bromine?

A

Red-brown

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What colour is iodine?

A

Grey

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What state is chlorine and fluorine at room temperature?

A

Gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What state is bromine at room temperature?

A

Liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What state is iodine at room temperature?

A

Solid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How does boiling point change down group 7 and why?

A

Increases. This is due to larger van der waals forces as atoms get larger.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why do halogens act as oxidising agents?

A

They gain an electron, so they become reduced and oxidise other things.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does electronegativity change down group 7?

A

Decreases because atoms get larger, so electrons are further from the nucleus. This means there is less attraction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How does oxidising power change down group 7?

A

Oxidising power decreases. This is because the outer electron shell gets further from the nucleus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What will be observed in a reaction with KBr and Cl2?

A

Orange solution as Br2 is formed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What will be observed in a reaction with KI and Cl2?

A

Brown solution formed as I2 is produced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What will be observed in a reaction with KI and Br2?

A

Brown solution formed as I2 is produced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a disproportionation reaction?

A

Where the same molecule is oxidised and reduced in the same reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Give an equation for the formation of bleach with state symbols.

A

2NaOH (aq) + Cl2 (g) -> NaClO (aq) + NaCl (aq) + H2O (l)

16
Q

What is the chemical formula of bleach?

A

NaClO

17
Q

Give the redox equation for chlorine + H2O with state symbols.

A

Cl2 (g) + H2O (l) = 2H+ (aq) + Cl- (aq) + ClO- (aq)

18
Q

Give the redox equation for chlorine and water in sunlight. Include state symbols.

A

Cl2 (g) + H2O (l) = 2H+ + 2Cl- + 0.5O2

19
Q

What are chlorate ions used for?

A

To kill bacteria. It can be put in water which makes it safe to drink.

20
Q

What is the disadvantage of water being used to kill drinking/swimming water?

A

Toxic

21
Q

Chlorine can be used to prevent the growth of which photosynthetic organism in water?

A

Algae

22
Q

What are the side effects of using chlorine in water?

A

Causes respiratory issues, irritates eyes and skin

23
Q

How does reducing power of halides change down the group and why?

A

Increases. This is because outer electrons get further from the nucleus and attraction gets weaker. This means its easier to lose an electron and donate it elsewhere (to reduce the other species).

24
Q

Give the equations for the reaction of NaF/NaCl with H2SO4 with state symbols.

A

NaF (s) + H2SO4 (aq) -> NaHSO4 (s) + HF (g)
NaCl (s) + H2SO4 (aq) -> NaHSO4 (s) + HCl (g)

25
Q

What observations could you make from NaF/NaCl + H2SO4?

A

White misty fumes.

26
Q

Why is there only one stage to the reactions of NaF/NaCl with H2SO4?

A

They are not powerful enough reducing agents

27
Q

Give the equation for NaBr + H2SO4 including state symbols.
Give the equation when one of the products of this reaction reacts with more H2SO4.

A

NaBr (s) + H2SO4 (aq) -> NaHSO4 (s) + HBr (g)
2HBr (aq) + H2SO4 -> Br2 (g) + SO2 (g) + 2H2O (l)

28
Q

What observations could you make from the reaction of NaBr and H2SO4?

A

Choking fumes of SO2 produced.
Orange fumes of Br2 produced.

29
Q

Why are there 2 stages to the reaction of H2SO4 and HBr?

A

Bromide ions are stronger reducing agents.

30
Q

Give the 3 stages of the reaction of NaI and H2SO4.

A

NaI (s) + H2SO4 (aq) -> NaHSO4 (s) + HI (g)
2HI (aq) + H2SO4 (aq) -> I2 (g) + SO2 (g) + 2H2O (l)
6HI + SO2 (aq) -> H2S (g) + 3I2 (s) + 2H2O (l)

31
Q

What observations can you make from the reaction of NaI and H2SO4?

A

H2S fumes, which smells of rotten eggs and solid iodine.