A2 Transition metal chemistry 1 - Phoenix Hoyle | Library

1

Copper Flow chart

Other Answer Choices:

copper(II) oxide / CuO

Copper (Cu)

1

T and V are the same type of chemical species. (i) Name this type of chemical species.

1

Explain why T is coloured while V is colourless. A detailed explanation of the fact that T is coloured is not required. (3)

The colour is due to transition of ______________  between split 3 d subshells / _____________  (1)  

in ___________  the d orbitals are partially filled so electron transitions are possible (1)
_________________ 
 in __________  the d orbitals are full and so no (electron) transitions are possible (1) __________________ 

Other Answer Choices:

Cu(II)

[Ar] 4s¹ 3d9

Cu(I)

orbitals

electrons

[Ar] 4s¹ 3d¹⁰

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(iii) Suggest an explanation for the change of V into T on shaking.

Cu(I) is _____________  to Cu(II) (1)  by ___________  in the air

Other Answer Choices:

reduced

oxygen

oxidised

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(c) The reaction between copper(I) iodide and sulfuric acid is a disproportionation. 

(i) Write the ionic equation for this disproportionation reaction.  

2CuI → Cu+ Cu2+ + 2I−

State symbols are not required. (1) 

(ii) Show that the reaction in (c)(i) is thermodynamically feasible. 

Eo cell ( = _________  − _________ ) = (______ )_________  (V)

The reaction is feasable because Eocell is _____________

Other Answer Choices:

-

negative

0.15

0.52

positive

0.37

+

1

Example added to notes.

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Chromium compounds and oxidation of alcohol


Eocell = EoR − EoL 
1.94 = EoR − (−0.61) 
EoR = 1.94 − 0.61= (+) _________ (V)
Therefore
The electrode system is number _______ 
(b) Write the overall equation for the reaction in the cell.  State symbols are not required.
______ C₂H₅OH + Cr₂O₇₂− + ______ H⁺ ⇌ 2Cr₃⁺ + ______ CH₃CHO + ______ H₂O

c) Write the ionic equation for the reaction of the aqueous solution of E with dilute sulfuric acid.
2CrO₄₂−         +       2H⁺  ⇌ Cr₂O₇2- + H₂O
___________               ___________    

Other Answer Choices:

3

1.33

orange

28

8

7

3

yellow

6