Metallic behaviour
The notes describe transition elements as metals that are generally hard, malleable and ductile. They are associated with face-centred cubic (FCC), hexagonal close-packed (HCP) and body-centred cubic (BCC) structures.
HALES ALENIA / TECHNICAL REFERENCE
IRIDIUM DETAILS.
A technical reference based on the supplied notes, covering key characteristics of the 3d transition series: metallic behaviour, periodic trends, oxidation states, ionization potentials and coloured compounds.
01 — OVERVIEWMETALLIC CHARACTER
THE CHARACTER
OF TRANSITION METALS.
The supplied document describes common physical characteristics and bonding behaviour across the transition elements.
Bonding characteristics
The document discusses both metallic and covalent bonding, linking covalent character with the presence of unfilled d-orbitals. It also identifies transition metals as good conductors of heat.
The source notes that some metals in Groups VII and IB are softer and more ductile than other transition metals. Group labels are retained as written in the supplied material.
02 — PERIODIC TRENDSATOMIC VOLUME & DENSITY
VOLUME, DENSITY
& STRUCTURE.
The following figures are transcribed from the source table. Some entries appear unclear in the original text extraction.
| ELEMENT | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn |
|---|---|---|---|---|---|---|---|---|---|---|
| Atomic volume (as transcribed) | 15.0 | 1.66 | 8.3 | 7.2 | 7.3 | 7.1 | 6.7 | 6.6 | 7.1 | 9.2 |
| Density (as transcribed) | 3.0 | 4.5 | 6.1 | 7.2 | 7.4 | 7.8 | 8.9 | 8.9 | 8.9 | 7.1 |
The original heading/unit for atomic volume and the second value for titanium are not reliably legible in the uploaded text. These figures are displayed as transcribed, not corrected or independently verified.
High density
The notes attribute comparatively high densities to the relatively low atomic volumes of d-block elements.
Lanthanide contraction
The document explains the similar sizes of 4d and 5d elements by the lanthanide contraction between lanthanum and hafnium.
Atomic size
Atomic size is expected to increase down a group, but the notes describe only a small size difference between the second and third transition series.
03 — CHEMICAL BEHAVIOUROXIDATION & BONDING
VARIABLE
OXIDATION STATES.
The supplied notes emphasise the role of d- and s-electrons in the variable oxidation states of transition metals.
Common oxidation states listed
The source lists the following states. Parentheses in the source indicate less common states.
Sc: +2, +3Ti: +2, +3, +4V: +2 to +5Cr: +2, +3, (+4), +6Mn: +2, +3, +4, (+6), +7Fe: +2, +3, (+4), (+6)Co: +2, +3, (+4)Ni: +2, (+3)Cu: +1, +2Zn: +2
Several symbols and oxidation-state entries are distorted in the uploaded OCR. Treat this list as a reading aid and check the original document before using it as a formal reference.
Electronic configuration
The notes use d0, d5 and d10 configurations to explain additional stability. Examples named in the source include Ti4+, Mn2+ and Ag+, associated with empty, half-filled and completely filled d-subshells respectively.
The document also states that higher oxidation states tend to become more stable on descending a group.
Acidic character
The notes describe increasing acidic character of metal oxides as the ionic character of the metal–oxygen bond decreases.
Bond character
A similar relationship is described for metal chlorides: decreasing ionic character is associated with increasing acidic character.
Reduction potentials
The source includes a list of standard reduction potentials and discusses the ability of some d-block metals to liberate hydrogen from dilute acids. Several signs and values are corrupted in the text extraction, so no numeric potential table is reproduced here.
04 — PHYSICAL PROPERTIESTHERMAL & IONIZATION TRENDS
ENERGY &
THERMAL RESPONSE.
Two further themes in the source are melting/boiling points and ionization potentials across the first transition series.
Thermal properties
The notes state that d-block elements generally have high melting and boiling points, with values tending to peak near the middle of a transition series. The explanation given is the availability of unpaired d-electrons for bonding. Zn, Cd and Hg are identified as exceptions with comparatively low melting and boiling points.
Ionization potentials
The source describes first, second and third ionization potentials as generally increasing from left to right across the 3d series, though not regularly. It attributes some irregularities to the stability of half-filled d5 and filled d10 configurations, particularly for chromium and copper.
| ELEMENT | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn |
|---|---|---|---|---|---|---|---|---|---|---|
| 1st ionization (kJ/mol) | 431 | 458 | 450 | 452.8 | 517.4 | 559.4 | 558 | 536.7 | 545.5 | 5806.4* |
| 2nd ionization (kJ/mol) | 1210 | 1210 | 1314 | 1535 | 1409.1 | 1461 | 1546 | 1653 | 1857.9 | 1633.3 |
| 3rd ionization (kJ/mol) | 2452 | 2628 | 2628 | 2787 | 2048.4 | 2757.4 | 3032 | 3139 | 3354 | 3632.7 |
*The zinc first-ionization entry appears as “5806.4” in the uploaded text and may contain an OCR/typing error. All values above are retained as supplied and have not been validated.
05 — COMPOUND APPEARANCECOLOUR & IONIC RADII
COLOUR IN
TRANSITION COMPOUNDS.
The source links the colours of many transition-metal ions with partially filled d-orbitals.
d-electron configuration
The notes state that ions with empty d0 or completely filled d10 configurations are generally colourless, while ions with partially filled d-orbitals are often coloured. The document uses hydrated cations from the first transition series as examples.
Blue — Cr2+ (as listed)
Green — V3+ (as listed)
Red — Ti3+ (as listed)
Yellow — Mn2+ (as listed)
Grey — Mn3+ (as listed)
Other examples are unclear in OCR
The source's colour-to-ion sequence is visibly garbled in places. The examples are reproduced cautiously from the readable portions and should be checked against the original scan.
Variation across the series
The final section states that ionic radii follow a trend similar to atomic radii, and that the radii of ions with the same charge generally decrease as atomic number increases.
| ION | Sc²⁺ | Ti²⁺ | V²⁺ | Cr²⁺ | Mn²⁺ | Fe²⁺ | Co²⁺ | Ni²⁺ | Cu²⁺ | Zn²⁺ |
|---|---|---|---|---|---|---|---|---|---|---|
| Radius (Å, as transcribed) | 0.90 | 0.85 | 0.83 | 0.69 | 0.75 | 0.71 | 0.69 | 0.67 | 0.62 | 0.69 |
The source extraction also begins a second row for 3+ ions, but the values are incomplete. It is not reconstructed here.