Brainscape's Knowledge GenomeTM

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


See full index

chemistry > topic 4 - inorganic chemistry and the periodic table > Flashcards

topic 4 - inorganic chemistry and the periodic table Flashcards

1
Q

what’s the ionization energy trend for group 2

A
  • ionization energy decreases down the group
  • each element going down has an extra electron shell
  • more shielding
  • valence electrons further from the nucleus which reduces the electrostatic force of attraction
    increased positive charge ( extra protons ) is overridden by the effect of shielding
  • making it easier to remove outer electrons
  • hence why reactivity increases going down the group
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is produced when group 2 elements react with water

A

metal hydroxide + hydrogen

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

what is produced when a group 2 metal is burnt in oxygen

A

solid white oxides

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

what happens when a group 2 metal reacts with chlorine

A

solid white chlorides

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

what is the reactivity of group 2 metals with water and what are the exceptions

A
  • metals react readily with water to form metal hydroxides , which dissolve
  • the hydroxide ions, OH- make these solutions strongly alkaline
  • beryllium oxide is an exception because it doesn’t react with water and berillyium hydroxide is insoluble
  • magnesium oxide is another exception because it only reacts slowly and hydroxide isn’t very soluble
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what’s the difference between alkalis and bases

A

bases are insoluble in water. on the other hand, alkali produces ions when dissolving in water

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

what’s the trends for oxides pH going down group 2

A

the oxides form more strongly alkaline solutions going down the group because the hydroxides get more soluble

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

what does it mean that group 2 oxides and hydroxides are bases

A

they will neutralise dilute acids forming solutions of the corresponding salts

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

magnesium oxides reaction with water

A

MO(s) + H2O (l) —> M(OH)2 (aq)

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

magnesium hydroxide reaction with water

A

M(OH)2(s) + H2O(l) —> M(OH)2(aq)

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

magnesium oxide reaction with dilute acid

A

MO(s) + 2HCl(aq) —> MCl2(aq) +H2O(l)

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

magnesium hydroxide reaction with dilute acid

A

M(OH)2(aq) + 2HCl(aq) —> MCl2(aq) + 2H2O(l)

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

what does solubility trend in a group depend on and what are the trends in group 2

A

the compound anion
- group 2 elements that contain singly charged negative ions ( e.g. OH-) increase solubility
- compound that contain doubly charged negative ions decrease in solubility down the group

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

what is the exception for solubility in group 2

A

most sulfates are soluble in water but barium sulfate is insoluble

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

what does sparingly soluble mean?

A

compounds like magnesium hydroxide that have very low solubility

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

what does thermal decomposition mean

A

thermal decomposition is when a substance breaks down ( decomposes ) when heated
- the more thermally stable a substance is, the more heat it will take to break it down

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

what’s a trend of thermal stability down a group ( carbonates and nitrates )

A
  • thermal stability increases down a group
  • the carbonate and nitrate ion and large negative ions ( anions ) and can be made unstable by the presence of a positively charged ion ( a cation )
  • the cation polarises the anion, distorting it. the greater the distortion, the less stable the compound
  • large cations cause less distortion than small cations as they have a lower charge density. so the further down the group, the larger the cations, the lower the charge density so the less distortion caused and the more stable the carbonate/nitrates compound
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what does it mean to have a lower charge density

A

the charge on the ion is spread out over a larger area

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

what’s the difference in thermal stability in group 2 and group 1

A

group 2 compounds are less thermally stable than group 1 compounds
- the greater the charge on the cation, the greater the distortion and the less stable the carbonate/ nitrate ion becomes. group 2 cations have a +2 charge, compared to a +1 charge for group 1 cations so group 2 carbonates and nitrates are less stable than those of group 1

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

how do group 1 carbonates decompose and what is the exception

A

group 1 carbonates are thermally stable so you can’t heat them enough with a bunsen burner to make them decompose ( they do compose at higher temperatures )
- except Li2CO3 which decomposes to Li2O and CO2

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

how do group 1 nitrates decompose

A

to form nitrite and oxygen
2MNO3 (s) —> 2MNO2(s) + O2 (g)
- except LiNO3 which decomposes to form Li2O, NO2, and O2

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

how do group 2 carbonates decompose

A

to form the oxide and carbon dioxide
MCO3(s) —> MO(s) + CO2(g)

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

how does group 2 nitrates decompose

A

form the oxide, nitrogen dioxide and oxygen
2M(NO3)2 (s) —> 2MO(s) + 4NO2 (g) + O2 (g)

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

how to test how easily nitrates decompose

A
  • how long it takes until a certain amount of oxygen is produced ( i.e. enough to relight a glowing splint )
  • how long it takes until an amount of brown gas ( NO2 ) is produced. this needs to be down in a fume cupboard because NO2 is toxic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

how to test how easily carbonates decompose

A

how long it takes for an amount of carbon dioxide to be produced. you test for carbon dioxide using lime water - which is a saturated solution calcium hydroxide. this turns cloudy with carbon carbon dioxide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

how to do a flame test

A

1) mix a small amount of the compound you are testing with a few drops of hydrochloric acid
2) heat a piece of platinum or nichrome wire in a hot bunsen flame to clean it
3) dip the wire into the compound/acid mixture. hold it in a very hot flame and note the colour produced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what colour does lithium produce in a flame test

A

red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what colour does sodium produce in a flame test

A

orange/yellow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what colour does potassium produce in a flame test

A

lilac

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what colour does rubidium produce in a flame test

A

red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what colour does caesium produce in a flame test

A

blue

32
Q

what colour does calcium produce in a flame test

A

brick red

33
Q

what colour does strontium produce in a flame test

A

crimson

34
Q

what colour does barium produce in a flame test

A

green

35
Q

how does a flame test produce colour

A

the energy absorbed from the flame causes electrons to move to a higher energy level. the colours are seen as the electrons fall back down to lower energy levels, releasing energy in the form of light.
the difference in energy between the higher and lower levels determines the wavelength of the light released - which determines the colour of the light

36
Q

what is the trend for electronegativity in halogens

A

decreases down the group

37
Q

what are the properties of fluorine

A

pale yellow, gas

38
Q

what are the properties of chlorine

A

green, gas

39
Q

what are the properties of bromine

A

red- brown , liquid

40
Q

what are the properties of iodine

A

grey , solid

41
Q

what’s the solubility of halogens

A

in their natural state they exist as covalent diatomic molecules. because they are non polar they have low solubility in water. ( but they dissolve easily in organic compounds like hexane )
iodine is insoluble in both dilute and concentrated
chlorine is soluble in both dilute and concentrated
bromine is insoluble in dilute but soluble in concentrated

42
Q

what colour does chlorine produce in water and hexane

A

virtually colourless in both

43
Q

what colour does bromine produce in water and hexane

A

yellow/ orange in water and orange/ red in hexane

44
Q

what colour does iodine produce in water and hexane

A

brown in water and pink/ violet in hexane

45
Q

what is the reactivity trend for halogens

A

decreases going down the group
gain electrons so are oxidizing agents
- atoms become larger
- greater distance from nucleus
- more shielding
- harder to gain electrons

46
Q

what is the halogen trends in electronegativity

A

decreases down group 7 due to the increase in number of electron shells and increase in distance between the nucleus and the bonding electrons

47
Q

what is the trends for melting and boiling points for halogens

A

increase going down the group
- increase in electron shells
- stronger london forces between the molecules
- this makes it harder to overcome the intermolecular forces

48
Q

why is fluorine and astatine hard to study

A

fluorine is a toxic gas and astatine is highly radioactive and decays quickly

49
Q

how can you see halogens relative oxidizing strength

A

can be seen in their displacement reaction with halide
- chlorine will displace both bromide and iodide ions
- bromine will displace iodide but not chloride ions
- iodine will not displace chloride or bromide ions

50
Q

what is the displacement reaction between halides

A

redox reaction
thing being displaced is oxidized and the thing that does the displacing is reduced
half equations:
Cl2 + 2e- —> 2Cl-
2Br - —> Br2 +2e-
(chlorine displaced bromine)

51
Q

reaction of potassium chloride (colourless) with chlorine water ( colourless ), bromine water (orange) and iodine solution ( brown )

A

no reaction in all

52
Q

reaction of potassium bromide (colourless) with chlorine water ( colourless ), bromine water (orange) and iodine solution ( brown )

A

chlorine = Cl2+2Br- —> 2Cl- +Br2 (aq)
—> mixture will turn orange
bromine and iodine = no reaction

53
Q

reaction of potassium iodide (colourless) with chlorine water ( colourless ), bromine water (orange) and iodine solution ( brown )

A

chlorine = Cl2 + 2I- —> 2Cl- + I2
—> turns orange
bromine = Br2 + 2I- —> 2Br- +I2
—> turns brown
iodine = no reaction

54
Q

how to make colour change easier to see ( halogen displacement reaction )

A

shake the reaction with an organic solvent like hexane
- the halogen present will dissolve in the organic solvent which settles out as a distinct layer above the aqueous solution

55
Q

equations for halogens disproportionation reaction with cold alkalis

A

X2 + + 2NaOH —> NAOX + H2O
ionic equation :
X2 + 2OH- —> OX- + X- + H2O

56
Q

how to produce bleach with equation

A

mix chlorine gas with cold, dilute aqueous sodium hydroxide —> sodium chlorate (I) solution ( bleach )
2NaOH (aq) + Cl2 (g) —> NaClO(aq) +H2O (l)

57
Q

3 uses of bleach

A
  • water treatment
  • bleach paper and textiles
  • cleaning
58
Q

equations for halogens disproportionation reaction with hot alkalis

A

3X2 + 6NaOH —> NaXO3 + 5NaX + 3H2O
ionic equation
3X2 + 6OH- —> XO3- + 5X- + 3H2O

59
Q

what happens when you mix chlorine with water

A

it undergoes disproportionation
end up with a mixture of hydrochloric acid and hypochlorous acid
Cl2(g)+ H2O(l) —> HCl (aq) + HClO (aq)
<—

60
Q

how can hypochlorous acid be used to kill bacteria

A

hypochlorous acid ionizes to make chlorate (I) ions ( also called hypochlorite ions )
HClO (aq) + H2O (l) —> ClO- (aq) +H3O(aq)
<—
chlorite (I) ions kill bacteria

61
Q

what happens when halogens react

A

they are reduced , the oxidize other substances
oxidize group 1 and 2 to produce halide salts

62
Q

equation and half equation of lithium reacting to fluorine ( group 1 + halide )

A

2Li(s) + F2 (g) — 2LiF (s)
Li : +1 oxidised - Li —> Li+ + e-
F : -1 reduced - F2 + 2e- —> 2F-

63
Q

equation and half equation of magnesium reacting to chlorine ( group 2 + halide )

A

Mg(s) + Cl2 (g) —> MgCl2 (s)
Mg : +2 oxidised - Mg —> Mg2+ + 2e-
Cl : -1 reduced - Cl2 + 2e- —> 2Cl-

64
Q

what is the trend of the reducing power of halides

A

halide ion can act as a reducing agent by losing an electron
decreases down the group
- ions get bigger so electrons are further away
- shielding weaker force of attraction

65
Q

reaction of halides and concentrated sulfuric acid

A

hydrogen halide

66
Q

features of hydrogen halides

A
  • colourless gases
  • can dissolve in water
  • produce misty fumes of acidic gas
  • turn blue litmus paper red
  • react with ammonia to give white fumes
67
Q

how to test for halides

A
  • add dilute nitric acid
  • add silver nitrate solution
  • observe precipitate colour
68
Q

what colour precipitate does fluoride ions form when reacted to nitric acid and silver nitrate

A

no precipitate

69
Q

what colour precipitate does chloride ions form when reacted to nitric acid and silver nitrate

A

white

70
Q

what colour precipitate does bromide ions form when reacted to nitric acid and silver nitrate

A

cream

71
Q

what colour precipitate does iodide ions form when reacted to nitric acid and silver nitrate

A

yellow

72
Q

why add ammonia after halide test

A

to make it easier to identity colour
- AgCl —> dissolves and gives a colourless solution
- AgBr —> remains unchanged if in dilute ammonia solution but will dissolve in concentrated ammonia solution to give a colourless solution
-AgI - doesn’t dissolve even in concentrated ammonia solution

73
Q

how to test for carbonates and hydrogen carbonates

A

add hydrochloric acid
fizz and give off CO2
test for CO2 using limewater
( turn cloudy )

74
Q

how to test for sulfates

A

add hydrochloric acid and barium chloride
- white precipitate formed

75
Q

how to test for ammonium compounds

A

ammonia gas is alkaline so you can check for it using red damp litmus paper turning it blue
add sodium hydroxide and gently heat
if ammonia is given off ammonium ions is present
- fume cupboard

76
Q

what does a reaction of a halide and concentrated sulfuric acid give

A

hydrogen halide

77
Q

Reaction of potassium fluoride or potassium chloride with sulfuric acid

A

KF(s) + H2SO4 (l)→ KHSO4(s) + HF(g)
KCL(s) + H2SO4 (l) —> KHSO4(s) + HCL (g)

Hydrogen fluoride (HF) or hydrogen chloride gas (HCL) is formed.
2)You will see misty fumes as the gas comes into contact with moisture in the i
But fuoride ions (F) and chloride ions (Cr) arent strond enough reducne
agents to reduce the sulfuric acid, so the reaction stops there.
3)It’s not a redox reaction - the oxidation numbers of the halide and sulfur stay the same (-1 and +6).

chemistry (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions