Tellurium (Te) is an element often recovered as a byproduct of copper and lead refining, valued for its characteristics in modern technology. To determine the number of neutrons, one must understand the fundamental structure of an atom. The neutron count for Tellurium is not a single number but a range, which is due to the existence of multiple natural forms of the element.
The Building Blocks of Matter
Every atom is composed of three primary subatomic particles: protons, neutrons, and electrons. Protons carry a positive electrical charge, electrons carry a negative charge, and neutrons are neutral. Protons and neutrons form the dense nucleus at the atom’s center, which contains almost all of the atom’s mass.
The number of protons within the nucleus defines an element’s identity and its placement on the periodic table. The total count of protons and neutrons combined is known as the Mass Number (A). To find the number of neutrons, a simple subtraction is performed: the number of neutrons equals the Mass Number (A) minus the Atomic Number (Z).
Tellurium’s Identity: The Atomic Number
Tellurium (Te) is classified as a metalloid, a type of element that exhibits properties of both metals and nonmetals. It is located on the periodic table with an Atomic Number (Z) of 52. This number signifies that every Tellurium atom must contain exactly 52 protons in its nucleus.
This fixed proton count defines Tellurium’s elemental identity. In an electrically neutral atom, the number of electrons orbiting the nucleus will also equal the number of protons (52 electrons). The challenge in determining the neutron count arises because the total mass of the atom is not fixed.
Determining the Neutron Count: The Isotope Factor
The number of neutrons in a Tellurium atom is not constant because the element exists in various forms called isotopes. Isotopes are atoms of the same element that have the same number of protons but a different number of neutrons, resulting in different Mass Numbers (A). Tellurium naturally occurs with eight different isotopes:
- Te-120
- Te-122
- Te-123
- Te-124
- Te-125
- Te-126
- Te-128
- Te-130
The number following the element symbol represents the Mass Number (A), which is used to calculate the neutrons. For example, the most abundant naturally occurring isotope, Tellurium-130 (Te-130), has a mass number of 130. Subtracting the atomic number (52) from the mass number (130 – 52) shows this specific isotope has 78 neutrons. The second most abundant isotope, Tellurium-128 (Te-128), has a mass number of 128, which translates to 76 neutrons (128 – 52).
The neutron count for naturally occurring Tellurium atoms ranges from 68 neutrons (Te-120: 120 – 52) up to 78 neutrons (Te-130). Since Te-128 and Te-130 together make up over 65% of all natural Tellurium, the most common neutron counts are 76 and 78.
Applications of Tellurium
Tellurium’s properties, including its semiconducting nature, make it valuable in modern technological applications. One of the most significant uses is in solar energy, specifically as a component of cadmium telluride (CdTe) thin-film solar cells. These cells are recognized for their high efficiency in converting sunlight into electrical power and are the second most utilized solar cell technology globally.
Tellurium is also widely used in metallurgy. Adding a small amount to copper and stainless steel alloys improves their machinability. When alloyed with lead, Tellurium increases the material’s strength and resistance to corrosion, finding use in battery plates and submarine cable sheaths. Compounds like bismuth telluride are components in thermoelectric devices used for cooling or power generation.