Brainscape's Knowledge GenomeTM

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


See full index

Chem Module 3 (3.1 The Periodic Table) > 3.1.2 Group 2 > Flashcards

3.1.2 Group 2 Flashcards

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

What are group 2 elements sometimes called

Why

A

The alkaline earth metals

Their oxides + hydroxides are alkaline

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

What block are group 2 metals in

What electrons are in their outer shell

A

S block

2s electrons in outer shell

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

When does group 2 atomic radius increase

Why

A

Going down the group

Each element has extra shell

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

What generally happens to melting points going down group
Why

What element is the exception
Why

A

Decrease
As as atoms get larger, the sea of delocalised electrons are further away from positive nuclei so strength of attraction gets smaller

Mg is exception
It’s lattice atom arrangement is different to other alkaline metals

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

What do group 2 elements do in all their reactions

A

Lose their 2 outer electrons to form doubly positively charged ions

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

What’s the 1st and 2nd IE Equations of any group 2 elememts

A

1st : M (g) -> M+ (g) + e-

2nd: M+(g) -> M2+ (g) + e-

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

Why does it get easier to remove the 2 outer electrons in reactions going down the group

A

As they get further away from the nucleus

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

What makes an element more reactive

A

The easier it is to remove electrons

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

What reactions occur when group 2 elements react with water

A

Redox

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

E.g of magnesium reacting with water

Calcium reacting with water

A

Mg(s) + 2H20(l) -> Mg(OH)2(aq) + H2(g)

Ca(s) + 2H2O(l) -> Ca(OH)2(aq) + H2(g)

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

What does calcium produce when reacting with water

What’s this used for

A

Limewater (slaked lime)

Used to treat acidic soil by farmers

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

What does magnesium produce when it reacts with water

What’s this used for

A

Milk of magnesia

Used as an antacid to treat indigestion

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

What does magnesium reacts slowly and fast with

A

Reacts slowly with cold water

Reacts fast with steam

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

What do all of the alkaline metal hydroxides look like

A

All white solids

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

What is solubility of metal hydroxides like going down group 2

A

Solubilities increase

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

What’s the pH of the hydroxide like if it’s more soluble

A

More soluble, the more OH- is released and the pH is higher

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How do you test for the sulfate ion

2 steps

A

Using BaCl2/Ba(NO3)2

  1. Acidity with dilute HNO3(aq)/dilute HCl (aq)
  2. Add Ba(NO3)2(aq)/BaCl2(aq)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What will form if the SO4 2- ion is present

What’s the equation

A

A white ppt of BaSO4

Ba2+(aq) + SO4 2-(aq) -> BaSO4(s)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What ions could interfere with the results of testing for sulfate ion, id it’s present

What’s the equation

A

CO3 2- ions would also produce a white pot with Ba2+

Ba2+(aq) + CO3 2-(aq) -> BaCO3(s)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Why is the acidifying step in place when testing for sulfate ions

A

To safeguard against CO3 2- ions interfering

Acid will destroy the carbonate ion by producing CO2 gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What do group 2 metals form when they react with oxygen

A

Metal oxide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What charge is the metal and oxygen in reactions with oxygen

A

Metal is 2-

Oxygen is 2+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What does Mg burn with in oxygen

A

Brilliant white light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What occurs in reactions with oxygen (R+O)

A

Oxidation of metal

Reduction of oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What reaction is when group 2 metals react with dilute acids

A

MASH

Metal + Acid -> Salt + Hydrogen

26
Q

What happens to the metal and H+ in the acid in reactions with dilute acids

A

Metal oxidised from 0 -> +2

Acids reduced from +1 -> 0

27
Q

What do group 2 metal oxides form when they react with water

A

Alkaline solutions of metal hydroxides

28
Q

What metal only reacts very very slowly with water to form a metal hydroxide

A

Magnesium

29
Q

What do reducing agents do

A

Donate/lose electrons

30
Q

What are classed as reducing agents

Why

A

Halides

As they can lose electrons

31
Q

General eq for halides acting as reducing agents

A

2X- -> X2 + 2e-

32
Q

What’s the weakest reducing agent

Strongest oxidising agent

A

F- weakest reducing agent

F2 strongest oxidising agent

33
Q

What’s the strongest reducing agent

Weakest oxidising agent

A

I- strongest reducing agent

I2 weakest oxidising agent

34
Q

What’s the halide ion like going down a group

A

Halide ion increases in size so outer electrons are less strongly attracted by nucleus and so ions can lose electrons more readily
Also increased shielding

35
Q

If a halogen is a strong oxidising agent what’s its halide like

A

Halide will be a weak reducing agent

36
Q

How can some halide ions be precipitated (2)

A
  1. Acidification with dilute nitric acid HNO3(aq)

2. Addition of silver nitrate solution AgNO3(aq)

37
Q

Why is HNO3 used to acidify the sample when testing for halide ions

A

As it removes cons that could effect the result

38
Q

If fluorine is produced what precipitate is there

A

None

39
Q

If chlorine is produced what precipitate is there

A

White

40
Q

If bromine is produced what precipitate is there

A

Cream

41
Q

If iodine is produced what precipitate is there

A

Yellow

42
Q

How can halides be further distinguished

A

By dilute, then concentrated ammonia (NH3)

43
Q

What solution does AgCl form when it dissolves with dilute ammonia solution

A

A colourless solution

44
Q

AgBr dissolves in concentrated ammonia solution but what is it insoluble in

A

Dilute ammonia

45
Q

Ionic Equations of testing for halide ions with chloride, bromide and iodide

A

Ag+(aq) + Cl-(aq) -> AgCl(s)

Ag+(aq) + Br-(aq) -> AgBr(s)

Ag+(aq) + I-(aq) -> AgI(s)

46
Q

How would u know if NaOH is present

A

Pungent smell

Turns red litmus paper blue

47
Q

What 2 things in the sample could affect the results as they react with AgNO3(aq)to produce white ppts

A 
Soluble carbonates (CO3 2-)
Hydroxides OH-
48
Q

When chlorine dissolves in water what does it form

What’s the equation

A

A mixture of hydrochloric acid,HCl and chloric acid, HClO

Cl2(g) + H2O(l) HCl(aq) + HClO(aq)

49
Q

What’s the process called when chlorine dissolves in water

what happens to the chlorine

A

Disproportionation

Chlorine has been simultaneously oxidised (lost electrons) and reduced (gained electrons)

50
Q

What does the presence of Cl2 and an equilibrium make the solution look

What does addition of alkali (OH- ions) cause to happen

A

Pale green

Adds water pushing the equilibrium to the right causing the green to fade

51
Q

What happens if addition of acid (H+ ions) occurs when chlorine water dissolves in water

A

The green intensifies and Cl2 has can be emitted which is TOXIC

52
Q

What’s an advantage of Cl2 in drinking water and swimming pools despite its toxicity

A

It’s dissolved in water in low concentrations to kill any bacteria

53
Q

What is chloric acid (HClO)

What does it also do

A

It’s an oxidant agent and a bleach

Kills bacteria

54
Q

What happens to blue litmus paper when testing for chlorine water

A

Blue litmus paper turns red (due to HCl), followed by white

55
Q

Why does litmus paper go white if chlorine waters present

A

As HClO is a bleach

56
Q

As chlorine isn’t very soluble in water, what can it easily be lost by

A

Evaporation

57
Q

What’s the active ingredient in household bleach as well as an oxidising agent

How is it produced

A

Sodium chlorate(l) (NaClO)

Produced when chlorine reacts with cold, dilute sodium hydroxide

58
Q

What’s the equation for chlorine reacting with sodium hydroxide
What type of reaction is this

A

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

Disproportionation of chlorine

59
Q

What can chlorine in tap water react with and do

A

Can react with methane (CH4) decaying vegetation and forming chlorinated hydrocarbons that are suspected carcinogens

60
Q

What could we get if we didn’t chlorinate water

E.g

A

Waterborne diseases e.g typhoid, cholera

61
Q

What are 2 alternatives to using Cl2 that aren’t as good

A

Ozone (O3)

UV light

Chem Module 3 (3.1 The Periodic Table) (3 decks)

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