Chromium is the 24th element on the periodic table where it is represented by the chemical symbol Cr. It is a shiny, gray, hard metal that is highly resistant to corrosion. It is mined as chromite ore and almost half of the world’s production comes from South Africa. Naturally occurring chromium is found as one of four stable isotopes. However, there are many other isotopes that have been identified.
How many isotopes does chromium have?
The four stable isotopes of chromium are known as 50Cr , 52Cr, 53Cr and 54Cr. However, 50Cr is thought to actually decay, but the half life is so long that it is considered to be stable. About 83% of the natural chromium found on Earth is 52Cr. There have also been 22 radioactive (unstable) isotopes of chromium discovered and all of these have been synthetically created. The most stable of these isotopes is 51Cr, with a half life of 27.7 days. The remaining unstable isotopes have half lives of less than 1 day, and most are actually shorter than 1 minute. The most unstable isotope of chromium is 66Cr with a half life of just 10 milliseconds. It is likely that most unstable isotopes of chromium will be discovered in the future.
Did you know?
53Cr has been used by scientists to estimate the levels of oxygen in the Earth’s atmosphere in the past.