Section 2 - Group 2 and Group 7 Elements Flashcards Preview

A Level Inorganic Chemistry > Section 2 - Group 2 and Group 7 Elements > Flashcards

Flashcards in Section 2 - Group 2 and Group 7 Elements Deck (57)
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1
Q

What type of ions do group 2 metals form?

A

2+ ions.

2
Q

What is the trend in atomic radius down group 2 and why?

A

Increases - extra electron shells are added.

3
Q

What is the trend in First Ionisation Energy down group 2 and why?

A

Decreases because…

  • electron shells increase
  • shielding occurs
  • electrons are futher from nucleus
4
Q

What is the trend in reactivity down group 2 and why?

A

Increases because…

  • First IE decreases
  • Easier to lose electrons
5
Q

What is the trend in mpts down group 2 and why?

A

Decreases…

  • they have metallic structures
  • metal ions get bigger but no. of electrons stays the same
  • larger ionic radius means the electrons are further from the nuclei
6
Q

What are group 2 elements reduced or oxidised when reacted?

A

Oxidised

7
Q

What is the trend in solubility when reacting Mg, Ca, Sr and Ba with OH-?

A

Increases

8
Q

What is the trend in solubility when reacting Mg, Ca, Sr and Ba with SO42-?

A

Decreases.

9
Q

What is the solubility of Mg(OH)2?

A

Sparingly soluble

10
Q

What is the solubility of BaSO4?

A

Insoluble

11
Q

What is the test for sulfate ions?

A

Add acidified barium chloride to a solution containing sulfate ions and a white precipitate of barium sulfate will form.

12
Q

Why must you acididfy the solution in the sulfate ions test?

A

To get rid of lurking sulfites or carbonates which would also produce a white precipitate

13
Q

What can be used to neutralise acid soils?

A

Calcium hydroxide (Ca(OH)2)

14
Q

What can be used to neutralise excess stomach acid?

A

Magnesium hydroxide (Mg(OH)2)

15
Q

Give the ionic equation for neutralisation:

A

H+(aq) + OH-(aq) —> H2O(l)

16
Q

Explain the barium meal:

A
  • a patient swallows a suspension of barium sulfate
  • it coats their tissues
  • it is opaque to x-rays so the tissues are visible
17
Q

Explain how magnesium can be used to extract titanium from its ore and give the equation:

A

TiCl4(g) + Mg2(g) —> Ti(s) + 2MgCl(l)

  • TiO2 (the main titanium ore) is converted to titanium chloride (TiCl4) by heating it with carbom in a stream of chlorine gas
  • the titanium chloride is then purified by fractional distillation
  • it is reduced by Mg in a furnace at almost 1000oC
18
Q

Explain how calcium oxide and calcium carbonate can be used to remove sulfur dioxide and give the equations:

A

CaO(s) + 2H2O(l) + SO2(g) —> CaSO3(s) + 2H2O(l)

CaCO3(s) + 2H2O(l) + SO2(g) > CaCO3(s) + 2H2O(l) + CO2(g)

  • powdered calcium oxide (CaO) and calcium carbonate (CaCO3)
  • a slurry is made by mixing these with water
  • it’s sprayed onto the flue gases
  • a solid waste product of calcium sulfite is formed
19
Q

What is the trend in electronegativity down group 7?

A

Decreases…

  • electrons are further from the nucleus
  • outer electrons are shielded by inner electrons
20
Q

What is the trend in bpts down group 7?

A

Increases…

  • relative mass increases
  • strength of Van der Waals increases
21
Q

What colour is F2?

A

Pale yellow

22
Q

What state is F2?

A

Gas

23
Q

What colour is Cl2?

A

Green

24
Q

What state is Cl2?

A

Gas

25
Q

What colour is Br2?

A

Red-brown

26
Q

What state is Br2?

A

Liquid

27
Q

What colour is I2?

A

Grey

28
Q

What state is I2?

A

Solid

29
Q

What is the trend in reactivity down group 7 and why?

A

Decreases…

  • atoms become larger
  • distance between electrons and nucleus increases
30
Q

A halogen will displace a halide ion from solution if the halide is _____ it in the periodic table.

A

Below

31
Q

What is the trend in oxidising strength down group 7?

A

Decreases

32
Q

Which ions will chlorine displace?

A

Br- and I-

33
Q

Which ions will bromine displace?

A

I-

34
Q

Which ions will iodine displace?

A

None

35
Q

What can be observed in a reaction between colourless chlorine water and colourless KCl solution?

A

No reaction

36
Q

What can be observed in a reaction between colourless chlorine water and colourless KBr solution?

A

Orange solution of Br2 formed

37
Q

What can be observed in a reaction between colourless chlorine water and colourless KI solution?

A

Brown solution of I2 formed

38
Q

What can be observed in a reaction between orange bromine water and colourless KCl solution?

A

No reaction

39
Q

What can be observed in a reaction between orange bromine water and colourless KBr solution?

A

No reaction

40
Q

What can be observed in a reaction between orange bromine water and colourless KI solution?

A

Brown solution of I2 formed

41
Q

What can be observed in a reaction between brown Iodine water and colourless KCl solution?

A

No reaction

42
Q

What can be observed in a reaction between brown Iodine water and colourless KBr solution?

A

No reaction

43
Q

What can be observed in a reaction between brown Iodine water and colourless KI solution?

A

No reaction

44
Q

What do chlorine and sodium hydroxide make?

A

Bleach

45
Q

Give the equation to make bleach:

A

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

46
Q

Is chlorine oxidised or reduced in the reaction to make bleach?

A

Both! This is called disproportionation

47
Q

What is it called when an element is both oxidised and reduced in a reaction?

A

Disproportionation

48
Q

Give 4 uses of bleach:

A
  • Water treatment
  • Bleaching paper
  • Bleaching textiles
  • Cleaning toilets
49
Q

Does chlorine get oxidised or reduced when it reacts with water?

A

Both - disproportionation

50
Q

Give the equation for the formation of chloride ions and chlorate ions from chlorine and water:

A

Cl2(g) + H2O(l) ⇌ 2H+ + Cl-(aq) + ClO-(aq)

51
Q

Give the equation for the decomposition of water in sunlight form chloride ions and oxygen:

A

2Cl2(g) + 2H2O(l) ⇌ 4H+ + 4Cl- + O2(g)

52
Q

Give 3 positives for the treatment of water with chlorine:

A
  • Kills disease-causing microorganisms
  • Some chlorine stays in water and prevents reinfection
  • Prevents growth of algae (and therefore bad tastes, smells and discolouration)
53
Q

Give 2 negatives for the treatment of water with chlorine:

A
  • Chlorine gas is harmful if inhaled
  • Liquid chlorine causes chemical burns
  • Could form chlorinated hydrocarbons which can cause cancer (but consider the health effects of unsafe drinking water)
54
Q

What is the trend in reducing power down group 7?

A

Increases…

  • Ions get bigger - electrons further from nucleus
  • more shielding
55
Q

Give the equation for the reaction of NaF with H2SO4?

A

NaF(s) + H2SO4(aq) —> NaHSO4(s) + HF(g)

56
Q

Give the equation for the reaction of NaCl with H2SO4?

A

NaCl(s) + H2SO4(aq) —> NaHSO4(s) + HCl(g)

57
Q
A