Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry OCR B Alevel > Elements From The Sea > Flashcards

Elements From The Sea Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

How do you calculate atom economy?

A

Mr of useful products/ total Mr of products x 100

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

What forms at the anode if the solution contains halide ions?

A

Halogen

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

What happens at the anode if it’s a sulphate or nitrate?

A

Oxygen is produced

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

What happens at the anode if its a hydroxide?

A

Oxygen produced from OH-

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

What is formed at the cathode if it is a group 1/2 metal or aluminium?

A

Hydrogen gas produced from water

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

What is produced at cathode if it’s a metal not in group 1 or 2 or aluminium?

A

Metal produced

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

What is produced at the cathode if it’s an acid?

A

Hydrogen from H+ ions

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

Define oxidation

A

Loss of electrons

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

Define reduction

A

Gain of electrons

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

What are the two steps of a iodine-thiosulfate titration?

A

Use an oxidising agent to oxidise as much iodine as possible
- excess acidic potassium iodide

Titration iodine with sodium thiosulfste to calculate moles of iodine produced

then calculate concentration of oxidising agent from this

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

What is the appearance of fluorine at room temp?

A

Pale yellow gas

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

What is the appearance of chlorine at room temp?

A

yellow-Green gas

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

What is the appearance of bromine at room temp?

A

Dark red volatile liquid

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

What is the appearance of iodine at room temp?

A

Shiny black solid

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

What is the trend in volatility of halogens? why?

A

Decrease down group

the strength of the IDID intermolecular bonds inceeases down group due to more electrons

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

What is the trend in solubility of halogens in water?

A

Decreases in solubility down group

17
Q

Colour of chlorine in water?

A

Pale green

18
Q

Colour of bromine in water?

A

yellow/Orange

19
Q

Colour of iodine in water?

A

Brown

20
Q

Are halogens more or less soluble in organic solvents than water?

A

More

21
Q

Colour of chlorine in hexane?

A

Pale green

22
Q

Colour of bromine in hexane?

A

Orange/brown

23
Q

Colour of iodine in hexane?

A

Violet

24
Q

Trend in reactivity of halogens? And 2 reasons?

A

Decrease in reactivity

Less shielding at top
So stronger attraction to extra electrons from nucleus

25
Q

How do you prepare HCl?

A

Add sulfuric acid or phosphoric acid to chlorine ions

26
Q

How do you prepare HBr and HI?

A

Add concentrated phosphoric acid to NaI/Br

27
Q

Trend in thermal stability of hydrogen halides

A

Decreases down group as bond strength decreases due to sheilding

28
Q

Acidity of halogen halides?

A

All strong acids apart from HF which is a weak acid

29
Q

Reaction of hydrogen halides with ammonia?

A

Produce ammonium halide= white fumes

30
Q

Reactions of hydrogen halides with sulfuric acid?

A

HCl- no reaction

HBr- SO2

HI- H2S

31
Q

what are properties of dynamic equilibrium?

A

must be a closed system

froward reaction is occuring at the same rate as back reaction

concentrations are constant

32
Q 
Kc>>1
kc> 1
kc=1
kc<1
kc<<1
A 
equilibrium lies far to the right
equilibrium lies to right
equilibrium is in he centre
equilibrium is to the left
equilibrium lies far to the left
33
Q

effect on Kc of
pressure
temperature
concentration of a reactant

A

changes Kc
changes Kc
no effect on Kc

34
Q

why doesnt changing the concentration of a reactant change the Kc

A

if a concentration term on the top becomes larger one on the bottom must also become larger to keep Kc constant so equilibrium position moves to left etc

35
Q

what are the uses of chlorine?

A

sterilising water by killing bacteria

bleaching

36
Q

what are the risks associated with storing and transporting chlorine?

A

it is toxic and corrosive - keep away from eyes and skin and when breathed in irritates respiratory system

is an oxidising agent so needs to be kept away from flamable materials

needs to be stored under pressure in small cylinders

37
Q

what is the solubility of
Ag Cl

AgBr

AgI

with ammonia?

A

soluble in dilute and concentrated ammonia

soluble in concentrated ammonia

ppt does not dissolve

Chemistry OCR B Alevel (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions