[Chemistry Class Notes] Neodymium Pdf for Exam

Neodymium Metal

Neodymium is an inorganic element with the atomic number 60. It is a part of the Lanthanide series. It is an inner transition element – the element in which the differentiating electron enters into the (n-2) f-subshell. It constitutes a separate block called f-block in the periodic table. It is a highly dense metal and has an atomic mass of 144.242 u. It cannot be found naturally in metallic form as the other lanthanides and is generally refined for usage. Lanthanides are termed as rare earth metals, but it is fairly common as other metals like copper, cobalt, etc. and is widely distributed in the Earth’s crust.

Use of Neodymium 

1. Neodymium metal, along with iron and boron, makes very powerful permanent magnets. They are cheaper, lighter and stronger. They are used in electronic gadgets like microphone, loudspeakers, guitar, computer hard disks and in-ear headphones.

2. Neodymium oxide Nd2O4 is used for colouring glass and making optical fibres as well as catalysts in polymerization reactions.

3. Neodymium glass is used to make lasers, astronomical work to produce sharp bands.

4. Also, used in eye surgery, cosmetic surgery, treatment of cancers and as laser pointers.

5. Neodymium salts are used as a colourant for various enamels.

6. Neodymium metal is used in cutting and welding of steel.

7. Also, used in cryocoolers due to its high specific heat capacity.

8. Its isotopes are used to construct changes in past ocean circulation.

9. Neodymium magnets can be used in bone repair and magnetic braces.

Hazards of Neodymium Metal

• It has no biological role, but it’s specks of dust and salts cause irritation to eyes.

• If it gets accumulated in the human body, it can damage your liver.

• Due to long exposure to neodymium, it can cause lung embolisms due to the fact that damps and gasses can be inhaled in air.

• It can cause damage to the cell membranes of the water animals and can influence their reproduction.

• Neodymium metal dust is combustible, and so has an explosion hazard.

• It also prevents clotting in the blood.

Characteristics of Neodymium Metal

• Atomic number: 60

• Atomic mass: 144.2 u

• Electronic configuration: [Xe]4f16s2

• Isotopes: 9

• Density: 7 g/cm3

• Melting point: 1024 oC

• Boiling point: 3074 oC

• Atomic Radius: 0.181 nm

• Oxidation states: +0, +2, +3, +4

• Natural occurrence: Primordial

• Crystal structure: Double hexagonal close packed

• Magnetic susceptibility: +5628 X 10-6 cm3/mol

Neodymium Sources

It is the second most abundant of the rare-earth element. It occurs as ores such as monazite- reddish-brown phosphate element that contains rare-earth elements and bastnaesite- one of a family of three carbonate-fluoride minerals.

The main mining areas include China, Sri Lanka, United States, Brazil, India and Australia.

Reactivity 

It is a highly electropositive and highly reactive element.

1. It tarnishes readily on exposure to air resulting in the fading of its silver-white lustres.

2. It burns in air to form its respective oxides.

3. It reacts with hydrogen to form non-stoichiometric hydrides.

4. It reacts with nitrogen on warming to form nitrides.

5. It reacts with nonmetals to form corresponding compounds.

6. It dissolves readily in warm water to liberate hydrogen.

Complex Formation

Neodymium being a lanthanoid, usually forms complexes with chelating ligands. Due to high electropositive nature, they possess little or no tendency to form complexes with pi-bonding ligands. The chelating ligands with which lanthanoids form complexes are generally beta-diketones such as acetylacetone, dibenzoyl methane, thenoyltrifluoroacetone, etc.

Example- [Nd(H2O)9] (BrO3)3

Neodymium Glass

Neodymium glass is produced by the addition of neodymium oxide in the glass melt. Usually, in daylight or incandescent light, it appears lavender and appears pale blue under fluorescent lighting. It may be used in colouring glass ranging in shades from pure violet to warm grey.

Neodymium changes the glass colour under different lighting conditions. Under daylight or yellow incandescent light, it changes the colour to reddish-purple whereas it changes the colour to blue under white fluorescent lighting, or greenish under trichromatic lightning. The collectors highly prize this colour-change phenomenon.

The chemical environment relatively little influences the colour, since the colour of neodymium depends upon forbidden f-f transitions. To obtain the best colour, minimize the iron-containing impurities in the silica, which is used to make the glass.

The melting properties of the glass would have affected since neodymium is a strong base. The lime content of the glass might have had to be adjusted due to its strong basic nature—light transmitted through these shows unusually sharp absorption bands.