Fern fronds are the leaves of ferns. They are a major organ of a fern and range significantly between species. Some species of tree ferns have fronds that grow as large as 5 m long while other species are limited to growing frond only 1 cm in length.
Cerium is a soft, ductile, silvery-white metallic chemical element with symbol Ce and atomic number 58. Cerium tarnishes when exposed to air, and it is soft enough to be cut with a knife. Cerium is the second element in the lanthanide series, and while it often shows the +3 state characteristic of the series, it also exceptionally has a stable +4 state that does not oxidise water.
Answer 1 On the Periodic Table, the symbol for Mercury is Hg. It comes from the Latin/Greek word, hydrargyrum.