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Flashcards in Chapter 8 Deck (66):
1

What colour are Group 2 compounds?

White or colourless

2

What are Group 2?

Alkaline earth metals

3

Are group 2 hard or soft metals?

Soft metals with low melting points

4

Are group 2 reactive or non reactive?

Reactive so usually found in compounds

5

What do Group 2 react with?

They undergo REDOX reactions with oxygen, water and dilute acids

6

What are Group 2 known as?

The halogens

7

What happens to Group 2 electron configurations during a reaction?

They react by loosing their outer 2 electrons to form 2+ ions

8

What type of agents are group 2 elements? What does that mean?

Reducing agents: a substance that causes another species to be reduced

9

What is produced when a Group 2 metal reacts with water?

They form an alkaline hydroxide and hydrogen gas

10

What can be observed when Group 2 elements react with water?

Fizzing/ effervescence and the solid dissapears

11

How does reactivity change down the group?

Reactivity increases down Group 2

12

What is observed during the REDOX reaction with oxygen and a halogen?

Burns with a bright white flame and white powder is produced

13

What is formed and seen when a halogen reacts with a dilute acid?

A salt is formed in addition to hydrogen gas, fizzing/ effervescence is seen and the solid disspears

14

How is shielding and atomic radius effected down Group 2?

They increase

15

How is nuclear attraction effected down Group 2?

It decreases

16

How is reactivity effected down Group 2?

Increases

17

How is the first ionisation energy effected down group 2?

Decreases

18

What is produced when group 2 oxides react with water?

Hydroxides

19

What is the typical pH of a Group 2 oxide?

Between pH 10-12

20

Are Group 2 oxides soluble? What happens when the solution becomes saturated?

Only slightly in water, once saturated a solid white precipitate forms

21

How is solubility in water effected by going down Group 2?

Increases down the group

22

How is alkalinity effected going down Group 2?

Increases

23

How is pH effected by going down Group 2?

Increases

24

What is a use for calcium hydroxide?

Reduce soil acidity

25

What is a use for magnesium hydroxide?

Neutralising excess HCl in the stomach

26

What is the outermost shell configuration for halogens?

ns2np5

27

Are halogens atomic or diatomic?

All diatomic

28

How stable are halogen as a element?

Very unstable to they are mostly found in metal compounds

29

What temperature can halogens be found?

Room temperature

30

What is the room temperature appearance of F2?

Pale yellow gas

31

What is the room temperature appearance of Cl2?

Pale green gas

32

What is the room temperature appearance of I2?

Red- Brown liquid

33

What is the room temperature appearance of Br2?

Shiny grey-black solid

34

What is the room temperature appearance of At2?

Never been seen

35

How are London forces effected down group 7?

Increased in strength

36

How is the energy required to break intermolecular bonds effected down group 7?

The bonds are stronger so more energy is required

37

How is boiling point effected down group 7?

Increased

38

How is the number of electrons effected down group 7?

Increased

39

What colour is solutions of halogens?

They all form different colours

40

Are halogens polar?

No they are non-polar so more soluble in non polar solvents like alkanes

41

What is the colour of Chlorine in water?

Very pale yellow

42

What is the colour of Bromine in water?

Orange

43

What is the colour of Iodine in water?

Brown

44

What is the colour of Chlorine in an alkane?

Pale Green

45

What is the colour of Bromine in an alkane?

Orange

46

What is the colour of Iodine in an alkane?

Violet

47

Why do two layers form if water are cyclohexane are mixed?

They are immiscible

48

What type of agent are halogen and what does this mean?

Halogen react by gaining an electron so are oxidising agents: they oxidise another species

49

Why does the halogens oxidising agent decrease down group 7?

Down the group the atomic radius and shielding increase, nuclear attraction decreases so ability to gain an electron decreases

50

Define disproportionation

A single element is both oxidised and reduced in the same reaction

51

What colour is the precipitate produced by AgCl (s) and silver nitrate?

White

52

What colour is the precipitate produced by AgBr (s) and silver nitrate?

Cream

53

What colour is the precipitate produced by AgI (s) and silver nitrate?

Yellow

54

What 4 things can you observe during a reaction?

1. Effervescence
2. Colour change
3. Precipitates
4. Identification

55

How can SO4 2- be identified?

By precipitation with Ba2+ (aq)

56

How can CO3 2- be identified?

By reaction with H+ (aq) to form CO2(g)

57

How can Cl-, Br-, I- be identified?

By precipitation with Ag+ (aq) / solubility in NH3 solution

58

How can NH4+ be identified?

Warm with NaOH(aq) to form NH3

59

What test can be used to identify the Carbonate ion, CO3 2- ?

Add a few drops of dilute nitric acid

Observe effervescence due to CO2 gas

60

What test can be used to identify the Sulfate ion, SO4 2-?

Add an equal volume of barium nitrate (aq)

Observe a white precipitate of barium nitrate

61

What test can be used to identify the Chloride ion, Cl-?

Add an equal volume of silver nitrate
(aq)

observe a white precipitate of silver chloride ( soluble in ammonia solution)

62

What test can be used to identify the Bromide ion, Br-?

Add an equal volume of silver nitrate (aq)

Observe a cream precipitate of silver bromide (soluble in concentrated ammonia solution)

63

What test can be used to identify the Iodide ion, I-?

Add an equal volume of aqueous silver nitrate

Observe a yellow precipitate of silver iodide ( in both dilute and concentrated ammonia solution)

64

What test can be used to identify the Ammonium ion, NH4+?

Warm with dilute sodium hydroxide and test any gas given off with damp red litmus paper.

Observe gas (ammonia) which turns litmus paper blue

65

Why must some ion tests be carried out in a specific order?

In order to avoid false positive results

66

What are the for ion tests and what order must you carry them out in?

1. Carbonate, CO3 2-
2.Sulphate, SO4 2-
3. Halides, Cl-, Br-, I-
4. Ammonium ion test