202Hg

202Hg is a stable isotope of the chemical element mercury (Hg) with mass number 202. It is one of mercury's seven stable isotopes and occurs naturally in mercury. The element has atomic number Z = 80, so 202Hg possesses 122 neutrons (N = A − Z = 202 − 80 = 122). Because 202Hg is an even–even nucleus, its ground-state spin is typically 0+ and it is non-radioactive.

Natural occurrence and isotopic context: In nature, mercury consists of a mixture of stable isotopes, including 196Hg, 198Hg, 199Hg, 200Hg, 201Hg, 202Hg, and 204Hg. 202Hg is not the single most abundant isotope but forms a meaningful portion of natural mercury. Isotopic compositions can be measured by mass spectrometry, and 202Hg can be enriched for specialized scientific applications.

Applications and significance: Stable isotopes such as 202Hg are used in isotopic-ratio studies and trace analyses in fields like geochemistry and environmental science. They also serve as calibration materials in mass spectrometry. Because mercury compounds are toxic, handling of isotopic samples, including 202Hg, requires appropriate safety precautions and containment.