ES - The halogens and atom economy Flashcards

1
Q

What is formed when silver ions react with halide ions?

A

A precipitate.

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

How do you test for halides?

A

Add dilute nitric acid to the sample to remove ions which might interfere with the reaction.

Then add silver nitrate solution.

If a precipitate is formed then you know that a halide is present.

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

What is the colour of the precipitate when silver nitrate is added to a fluoride ion?

A

No precipitate as AgF is soluble.

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

What is the colour of the precipitate when silver nitrate is added to a chloride ion?

A

White.

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

What is the colour of the precipitate when silver nitrate is added to a bromide ion?

A

Cream.

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

What is the colour of the precipitate when silver nitrate is added to a Iodine ion?

A

Yellow.

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

What do you add to the silver nitrate and halide solution if it is hard to identify the colour?

A

Ammonia solution.

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

What will happen when ammonia solution is added to AgCl?

A

Precipitate dissolves in dilute ammonia solution to give a colourless solution.

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

What will happen when ammonia solution is added to AgBr?

A

Precipitate remains unchanged if dilute ammonia solution is added, but will dissolve in concentrated ammonia solution to give a colourless solution.

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

What will happen when ammonia solution is added to AgI?

A

Precipitate does not dissolve, even in concentrated ammonia solution.

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

Why is chlorine dangerous?

A

It is toxic and corrosive so must be kept away from skin and eyes.

It is also harmful if breathed in - irritates respiratory system.

Increases fire risk as it is an oxidising agent.

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

Why does chlorine increase fire risks?

A

Because it is an oxidising agent.

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

Why should chlorine be kept away from flammable materials?

A

It is an oxidising agent so can increase the fire risk.

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

How is chlorine stored?

A

As liquid under pressure in small cylinders.

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

How is chlorine useful?

A

It is used in water treatment as adding chlorine sterilises water making it safe to drink/swim in - so we don’t get nasty and potentially dangerous infections.

It kills disease-causing microorganisms such as bacteria.

Used to make bleach.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is atom economy?

A

A measure of the efficiency of a reaction.

17
Q

What is a by-product?

A

Another an incidental or secondary product made in the manufacture or synthesis of something else.

18
Q

What is a co-product?

A

Another product produced in the reaction.

19
Q

Are by-products bad?

A

Yes

20
Q

Are co-products bad?

A

Can be good or bad.