pmt transition elements

Question 1

What are transition metals?

Answer 1

Transition metals are elements in the d-block of the periodic table that form one or more stable ions with a partially filled d-orbital.

Question 2

How do transition metals form positive ions?

Answer 2

Transition metals lose electrons to form positive ions, with the s-orbital electrons being removed first.

Question 3

What are the common physical properties of transition metals?

Answer 3

All transition metals have similar atomic radius, high densities, and high melting points.

Question 4

What are the special chemical properties of transition metals?

Answer 4

Transition metals can form complexes, form coloured ions in solution, exhibit variable oxidation states, and act as good catalysts.

Question 5

Why do transition metals have variable oxidation states?

Answer 5

Transition metals have variable oxidation states because the 4s and 3d orbitals are very close in energy levels, allowing electrons to be lost from both orbitals.

Question 6

What is the electron configuration of Scandium?

Answer 6

Scandium: atomic number 21 - [Ar] 4s² 3d¹

Question 7

What is the electron configuration of Nickel?

Answer 7

Nickel: atomic number 28 - [Ar] 4s² 3d⁸

Question 8

What is the electron configuration of Iron?

Answer 8

Iron: atomic number 26 - [Ar] 4s² 3d⁶

Question 9

What is the electron configuration of Fe²⁺?

Answer 9

Fe²⁺ - atomic number 26 (=24 electrons) - [Ar] 4s⁰ 3d⁶ or [Ar] 3d⁶

Question 10

What is the electron configuration of Vanadium?

Answer 10

Vanadium: atomic number 23 - [Ar] 4s² 3d³

Question 11

What is the electron configuration of V²⁺?

Answer 11

V²⁺ - atomic number 23 (=21 electrons) - [Ar] 4s⁰ 3d³ or [Ar] 3d³

Question 12

What are the exceptions to the filling order of orbitals in transition metals?

Answer 12

Copper and chromium are exceptions to the rule that the 4s subshell is filled before the 3d subshell.

Question 13

What is the electron configuration of Chromium?

Answer 13

Chromium has 24 electrons and its actual electron configuration is [Ar] 4s¹ 3d⁵.

Question 14

What is the electron configuration of Copper?

Answer 14

Copper is more stable with the configuration [Ar] 4s¹ 3d¹⁰.

Question 15

What role do transition metals play as catalysts?

Answer 15

Some transition metals and their compounds display catalytic behaviour, making them useful in industry.

Question 16

What is an example of a catalyst involving Cu²⁺?

Answer 16

Cu²⁺ is a catalyst for Zn and acids.

Question 17

What does MnO₂ catalyze?

Answer 17

MnO₂ catalyzes the decomposition of H₂O₂.

Question 18

What are ligands in complex ions?

Answer 18

Ligands are molecules/ions with a lone electron pair that can form a dative bond with the central metal ion.

Question 19

What are examples of ligands?

Answer 19

Examples of ligands include: Cl⁻, H₂O, NH₃.

Question 20

How are ligands classified?

Answer 20

Ligands are classified based on the number of bonds they form: Monodentate (1 bond), Bidentate (2 bonds), Hexadentate (6 bonds).

Question 21

What is the coordination number?

Answer 21

The coordination number is the total number of coordinate bonds with the central metal ion.

Question 22

What is the common coordination number for silver complexes?

Answer 22

Silver complexes typically have a coordination number of 2.

Question 23

What is the common coordination number for platinum complexes?

Answer 23

Platinum complexes usually have a coordination number of 4.

Question 24

What causes color in transition metals?

Answer 24

Color in transition metals is due to light absorption caused by electron transitions between split d-orbitals.

Question 25

What factors influence the color of transition metal complexes?

Answer 25

Factors influencing color include coordination number, ligand type, and oxidation state.

Question 26

What is the shape and bond angle of octahedral complexes?

Answer 26

Octahedral complexes have a bond angle of 90°.

Question 27

What is the shape and bond angle of tetrahedral complexes?

Answer 27

Tetrahedral complexes have a bond angle of 109.5°.

Question 28

What is the shape and bond angle of square planar complexes?

Answer 28

Square planar complexes have a bond angle of 90°.

Question 29

What is Cisplatin?

Answer 29

Cisplatin is a cis-isomer of a square planar complex used in cancer therapy.

Question 30

What is ligand substitution?

Answer 30

Ligands in a complex can be exchanged, leading to changes in coordination and geometry.

Question 31

What is an example of ligand substitution in biology?

Answer 31

Haem in haemoglobin is an example involving multidentate ligands, with ligand substitution affecting oxygen transport.

Question 32

What is the chelate effect?

Answer 32

Replacing monodentate ligands with polydentate ligands increases stability due to a positive entropy change.

Question 33

What are precipitation reactions?

Answer 33

Reactions of metal aqua ions with NaOH/NH₃ form coloured precipitates.

Question 34

What do color changes in precipitation reactions indicate?

Answer 34

Color changes indicate ion presence.

Question 35

What are redox reactions in transition metals?

Answer 35

Transition metals can exhibit variable oxidation states, undergoing redox reactions with observable colour changes.

Question 36

What is an example of a redox reaction involving Iron?

Answer 36

Iron: Fe²⁺ (pale green) to Fe³⁺ (orange/brown).

Question 37

What is an example of a redox reaction involving Chromium?

Answer 37

Chromium: Cr⁶⁺ (Cr₂O₇²⁻) to Cr³⁺ and Cr²⁺.

Question 38

What is an example of a redox reaction involving Copper?

Answer 38

Copper: Cu²⁺ to Cu.

Question 39

What are qualitative analysis tests for anions?

Answer 39

Tests for anions include Carbonate (CO₃²⁻), Sulfate (SO₄²⁻), Halides.

Question 40

What are qualitative analysis tests for cations?

Answer 40

Tests for cations include Ammonium (NH₄⁺) and transition metals.

Question 41

draw an octahedral compex

Answer 41

Question 42

draw a tetrahedral complex

Answer 42

Question 43

draw cis-platin

Answer 43