Inorganic Chemistry Flashcards

1
Q

Groups 1 and 2

A

All have the highest energy electron in the s subshell

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

Group 2 reacting with O2

A
  • except Be, they all react vigorously, producing a bright flame
  • 2M + O2 -> 2MO
  • Ba + O2 -> 2BaO2
  • contains a peroxide ion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Peroxide ion

A

(O2)2-

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

2Mg + O2 -> 2MgO

A
  • bright white flame

* used in fireworks and flames

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

Ca + Sr with O2

A

red flames

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

Ba + O2 -> 2BaO2

A

Green flame

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

Group 2 reactions with water

A
  • less reactive than the corresponding group 1 elements
  • Be does not react with steam
  • Mg reacts v. slowly w/ cold water and does react w/ steam
  • Ca, Sr and Ba all react w/ cold water with increasing vigour
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Mg (s) + H2O (g)

A

-> MgO(s) + H2 (g)

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

Ca (s) + 2H2O

A

-> Ca(OH)2 + H2(g)

Calcium hydroxide is only sparingly soluble in water, so a thick white suspension accompanies the effervescence

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

Sr(s) + 2H2O (l)

A

-> Sr(OH)2 + H2 (g)

Strontium hydroxide is slightly soluble in water

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

Ba(s) + 2H2O (l)

A

-> Ba(OH)2 + H2 (g)

Barium hydroxide is soluble in water

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

Group 2 reactions with chlorine

A

All form chlorides

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

Group 2 oxide reacting with water

A
  • BeO is not attacked by water

* others are ionic; react to form hydroxides

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

Group 2 oxides reacting with dilute acids

A

All produce salt and water

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

Group 2 hydroxides (bases)

A

React with acids in neutralisation to form salt and water

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

Group 2 sulphate solubility

A

Solubility decreases down the group

MgSO4 -> soluble
CaSO4 -> slightly soluble
SrSO4 -> insoluble
BaSO4 -> insoluble

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

Testing for sulphate ions

A
  • used because BaSO4 is highly insoluble
  • if BaCl2 is added to a solution containing sulphate ions, a white ppt is produced

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Group 2 hydroxide solubility

A
  • solubility increases down the group
  • Ca(OH)2 is not very soluble in water; much more soluble than CaCO3
  • when CO2 is passed through Ca(OH)2, it forms insoluble CaCO3 suspension, turning limewater cloudy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Indicator of carbonate thermal stability

A

Time taken for gas evolved to turn limewater cloudy

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

All group 1 carbonates are…

A

… thermally stable up to Bunsen temperatures; smaller charge density; lower polarising power

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

Lithium and group 2 carbonates thermally decompose to form

A

Metal oxide + CO2

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

Stability trend down Group 2

A
  • more stable
  • charge density decreases
  • smaller polarising power
  • cannot draw oxygen towards it as easily
  • does not distort the C-O bond to the same extent
  • need more vibrational energy as the bond has not been as weakened
  • harder to release the CO2 and form the metal oxide
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

All nitrates…

A

… decompose

24
Q

Group 1 nitrates except Li

A

Break down to form

Metal nitrite + oxygen

25
Q

Lithium and group 2 elements…

A

… break down to a greater extent (because they have higher polarising power) to form

Metal oxide + nitrogen dioxide + oxygen

26
Q

Flame test theory

A

Electrons are pushed to a higher energy level when heated; when they drop back down, they give out their energy in the form of light

27
Q

Flame colours

A
Lithium = red 
Sodium = yellow 
Potassium = lilac 
Calcium = brick red 
Strontium = crimson 
Barium = apple green
28
Q

MP and BP trend down halogen group

Don’t confuse with relativity!!!

A
  • increases
  • more electrons
  • more idids
  • more energy needed to overcome the forces
29
Q

Trend for electronegativity down halogen group

A
  • decreases
  • atomic radius increases
  • bonding pair is further from nucleus with greater inner shielding
  • harder to pull the electron towards the nucleus
30
Q

Reactivity of the halogens depends upon

A

How strongly the electron is drawn into the vacant position in their outer-shell

31
Q

Reactivity trend down halogen group

A
  • decreases
  • atomic radius increases
  • greater distance and more shielding between incoming electron and the nucleus
  • attraction decreases
  • illustrated by displacement reactions
32
Q

Cl2 + 2KBr -> Br2 + 2KCl

A
Cl2 = chlorine water; colourless
2KBr = potassium bromide; colourless 
Br2 = bromine water; orange 
2KCl = potassium chloride; colourless 

Bromine présence is proven by adding an organic solvent into which bromine dissolves preferentially, turning red

33
Q

Trend in oxidising capacity going down the halogen group

A
  • chlorine is the strongest oxidising agent
  • wants to gain electrons!
  • smallest atomic radius
  • least distance and shielding
  • attraction of incoming e-s to the nucleus is greater

As halogens tend to gain electrons (electronegative); they tend to be oxidising agents

34
Q

Trend in reducing capacity going down the halogen group

A
  • iodine is the best reducing agent
  • wants to lose e-
  • largest atomic radius
  • greatest distance and shielding
  • easily loses outer e-
35
Q

Halogen reactions with metals

A
  • tend to be reactive
  • vigour decreases with reduced reactivity
  • less exothermic as atomic number increases
36
Q

Cl2 + H2

A

-> 2HCl

Explosive in sunlight

37
Q

Br2 + H2

A

-> 2HBr

Requires heat + platinum catalyst

38
Q

I2 + H2

A

V slow- reaction does not go to completion

39
Q

Disproportionation of chlorine

A

Cl2 + H2O <=> HOCl + HCl

Used in water treatment as HOCl contains chlorate(I)ion, which has strong anti-bac action, sterilising the water

Reversible; quantités of chlorate(I)ions are quite small -> it is safe to drink the water

Shifted right by removing acid products, using NaOH alkali

40
Q

Cl2 + NaOH

Cold!

A
  • -> NaOCl + NaCl
  • produces a much higher concentration of chlorate(I)
  • used in bleach
41
Q

3Cl2 + 6NaOH

A

-> NaOCl3+ 5NaCl + 3H20
• 5 chlorine atoms take an electron to form ions (in NaCl)
• chlorine losing 5 electrons goes to 5+ (in NaClO3)

42
Q

Iron is a …

A

… transition metal; can form compounds of iron(II) and iron(III)

43
Q

Solutions containing iron(II)

A

Pale green

44
Q

Solutions containing iron(III)

A

Yellow

45
Q

Cl2 + Fe2+

A

-> 2Cl- + 2Fe2+

Pale green -> yellow
Could also use bromine as oxidising agent, but not iodine

46
Q

Conc. H2SO4

A
  • oxidising agent

* when added to potassium Hamite, hydrogen halide is formed

47
Q

KCl(s) + H2SO4 (aq)

A

-> KHSO4 (aq) + HCl (g)

Steamy white fumes
Effervescence
Wet litmus turns blue -> red

Chloride is not a very strong reducing agent -> holds e-s

48
Q

KBr (s) + H2SO4 (aq)

A

-> KHSO4 (aq) + HBr (g)

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

49
Q

KI (s) + H2SO4 (aq)

A

-> KHSO4 (aq) + HI

H2SO4 (aq) + 2HI (g) -> I2 (s+g) + SO2 + 2H2O

50
Q

Halide test

A

1) dissolve in water
2) acidity with dilute HNO3
3) add AgNO3 (aq)
4) identify silver halide precipitate by colour

Ag+ (aq) + X- (aq) -> AgX (s)

51
Q

Hydrogen halides + water

A
  • soluble
  • dissociate into ions, forming acidic solutions
  • HX (aq) -> H+ (aq) + X- (aq)
52
Q

Hydrogen halides + ammonia

A
  • when gaseous hydrogen halides come into contact with gaseous ammonia, ammonium halide (dense white smoke) is produced
  • HX (g) + NH3 (g) -> NH4X (g)
53
Q

Carbonate and hydrogencarbonate chemical test

A

• adding dilute acid forms CO2 (effervescence)

  • (CO3)2- (aq) + 2H+ (aq) -> H2O (l) + CO2 (g)
  • HCO3- (aq) + H+ (aq) -> H2O (l) + CO2 (g)
  • when CO2 is bubbled through limewater, it goes cloudy due to CaCO3(s) formation
  • Ca(OH)2 (aq) + CO2 (g) -> CaCO3(s) + H2O (l)
54
Q

Sulphate test

A
  • add dilute HCl
  • if no reaction, add a few drops of BaCl2 (aq)
  • forms a white precipitate

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

55
Q

Ammonium test

A
  • warm with NaOH(aq) -> produces NH3
  • NH3 dissolves
  • test w/ damp red litmus
  • turns blue

• NH3(g) + H2O(l) -> NH4+ + OH-

Alkali!