Introduction to Yttrium Element
Yttrium is the rare earth transition metal located in group number 3 and period 5 of the periodic table. Its atomic number is 39 whereas its atomic mass is 88.90. There are 39 electrons in a single neutral atom of yttrium.
The nucleus of the yttrium contains 39 protons and 50 neutrons. The element yttrium is represented by the symbol “Y”.
Naming and History
Yttrium was named after the valley Ytterby in Sweden from where it was discovered.
- Carl Arrhenius
In 1787, Carl Arrhenius found coal-like material in quartz near Ytterby valley in Stockholm – the capital of Sweden. He thought he had found a new mineral of tungsten as he reported that the mineral contain iron and tungsten. He named it Ytterbite.
- Johan Gadolin
He sent the specimen to Johan Gadolin in Finland. In 1794, he carried out a detailed analysis and concluded that it contained 12% iron oxide, 19% alumina, 31% silica, and 38% unknown earth material.
- Anders Ekeberg
In 1797, another Swedish chemist Anders Ekeberg confirmed the observations and results of Gadolin. He suggested the name Yttria for the unknown rare earth transition metal which later became Yttrium.
- Frederick Wohler
In 1828, Frederick Wohler first isolated the yttrium metal by reacting yttrium oxide with potassium.
- Carl Mosander
In 1843, Carl Mosander investigated the oxides of yttrium and found three oxides. These were yttrium, terbium and erbium oxides.
- Frank Spedding
In 1953, Frank Spedding produced yttrium metal of high purity by using ion exchange techniques.
Occurrence of Yttrium
Yttrium never exists as a free element in nature. It is present in minerals and ores of rare earth metals. Some yttrium is present in uranium ores. Today, most of the yttrium is obtained by the process of ion exchange from monazite sand. Monazite is a mineral rich in rare earth elements.
The other yttrium containing minerals are barnasite, fergusonite, and samarskite.
Properties of Yttrium
Yttrium is soft, highly crystalline, silverish- gray rare earth transition metal. Its compounds are mostly colorless but oxides are yellow, white, and other colors. It usually exists as a trivalent ion Y 3+. It has a high affinity for oxygen.
It is fairly stable in the air due to the formation of thin oxide film on its surface. It oxidizes on heating. Yttrium reacts with mineral acids. In reaction with water, it decomposes it eliminating hydrogen plus forming yttrium hydroxide.
Finely divided yttrium is very unstable in the air and easily ignites. The melting point of yttrium is 1522°C and its boiling point is 3345°C. It has a density of 4.47 grams per cubic centimeter and exists as solid at room temperature.
Yttrium in Biological Systems
There is no known significant role of yttrium in living systems. Its salts are soluble and mildly toxic.
Uses of Yttrium
- Metallic yttrium is not widely used but its compounds are of good importance.
- Yttrium compounds are used to produce red phosphor which is used in color televisions.
- Yttrium is used in aluminium and magnesium alloys to increase their strength.
- Yttrium aluminium garnet (YAG) is used in specific lasers which cut through the metals.
- It is used in LED lights for white color.
- It is used in making microwave filters for radar for blocking certain frequencies and is widely used in communication devices and satellites.
- Yttrium is alloyed with chromium and aluminium to make heat-resistant metal.
- It is used as a catalyst in ethylene polymerization.
- Yttrium barium copper oxide is of great importance and is used in the production of high-temperature super conductors and conducts electricity without any loss of energy.
- Yttrium oxide is used in the manufacturing of camera lenses and a special type of heat and shock-resistant glass.
Isotopes of Yttrium
From mass numbers 79 to 103, almost 25 isotopes of yttrium are known for their half-lives. Yttrium- 89 is the only naturally occurring stable isotope.
- The radioactive isotope of yttrium – Yttrium- 90 is used in the diagnosis and treatment of various cancers. It is used in precise medical needles to sever pain-transmitting nerves in the spinal cord.