Properties of transition metalsEdexcel A-Level Chemistry: Subtopic test

1. 1
   A student is classifying the period 4 d-block elements, from scandium (Z = 21) to zinc (Z = 30), using their atomic numbers.

   (a)

   What is the electronic configuration of an Fe³⁺ ion (Z = 26)?

   [1 mark]

   • A[Ar]3d⁵
   • B[Ar]3d³4s²
   • C[Ar]3d⁶
   • D[Ar]3d⁴4s¹

   (b)

   Which of these elements is NOT a transition metal?

   [1 mark]

   • ATitanium
   • BZinc
   • CManganese
   • DNickel

   (c)

   Explain why scandium is a d-block element but is not classified as a transition metal.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   Copper (Z = 29) is used in electrical wiring and forms compounds containing Cu⁺ ions and Cu²⁺ ions.

   (a)

   What is the electronic configuration of a copper atom?

   [1 mark]

   • A[Ar]3d⁹4s²
   • B[Ar]3d¹⁰4s²
   • C[Ar]3d¹⁰4s¹
   • D[Ar]3d⁹4s¹

   (b)

   What is the electronic configuration of a Cu²⁺ ion?

   [1 mark]

   • A[Ar]3d¹⁰
   • B[Ar]3d⁹4s²
   • C[Ar]3d⁸4s¹
   • D[Ar]3d⁹

   (c)

   Cu⁺ ions have a full 3d subshell. Explain why copper is nevertheless classified as a transition metal.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   Vanadium (Z = 23) forms compounds in which its oxidation number is +2, +3, +4 or +5, for example in VO₂⁺, which contains vanadium(V). Calcium (Z = 20) forms compounds in which its oxidation number is only +2.

   (a)

   Deduce the full electronic configuration of a vanadium atom and of a V³⁺ ion, and state the number of 3d electrons in the vanadium in VO₂⁺.

   [3 marks]

   (b)

   Explain why vanadium shows several oxidation numbers but calcium shows only +2.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A teacher gives a class the elements scandium (Z = 21), manganese (Z = 25) and zinc (Z = 30), which are all d-block elements. Manganese forms compounds in which its oxidation number is +2, +4 or +7, for example in Mn²⁺, MnO₂ and MnO₄⁻. Scandium forms only Sc³⁺ compounds and zinc forms only Zn²⁺ compounds.

   (a)

   Deduce the electronic configurations of a manganese atom and an Mn²⁺ ion, state the oxidation number of manganese in MnO₂ and MnO₄⁻, and explain why manganese shows several oxidation numbers.

   [6 marks]

   (b)

   A student claims that all d-block elements are transition metals and show variable oxidation numbers. Evaluate this claim using scandium, manganese and zinc.

   [6 marks]

   Total for question 4: 12 marks

End of questions