What are rare earth elements?
Q: What are rare earth elements?
A: Rare earth elements are a set of seventeen chemical elements, including fifteen lanthanides plus scandium and yttrium.
Q: Why are scandium and yttrium considered rare earth elements?
A: Scandium and yttrium are considered rare earth elements because they are often found in the same ore deposits as the lanthanides and have similar chemical properties.
Q: Are rare earth elements extremely rare on Earth?
A: No, rare earth elements are not extremely rare on Earth. They were called this because they are spread very evenly over the Earth, so it is hard to find a lot in one place.
Q: What makes promethium rare?
A: Promethium is rare because it is radioactive, and it decays.
Q: Is cerium a rare earth element?
A: Yes, cerium is one of the lanthanides and is considered a rare earth element. However, it is the 25th most common element in the Earth's crust.
Q: Are most rare earth elements found in concentrated or pure forms?
A: No, most rare earth elements are not found in concentrated or pure forms.
Q: How many of the seventeen rare earth elements are lanthanides?
A: Fifteen of the seventeen rare earth elements are lanthanides.
