helium is in period 1, group 18.
He is the symbol for the element helium.
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roentgenium
dubnium
Germanium
Every type of atom currently know to man. It consists of 118 elements, though the number is always changing.
Most of the symbols on the Periodic Table have symbols for the latin name of the element. AU = Aureum = Gold.
Dmitri Mendeleev was the inventor of the periodic table of elements.
It's a table listing the elements, organized in columns of similar types of elements with respect to their chemical bonding characteristics, based on their atomic numbers and electron configurations.
All elements from atomic number 84 (Polonium - Po) and onwards are radioactive, although ones that have not been observed cannot be confirmed.
SI is Sulphur and Iodine, Si is Silicon. Tehy are both different elements on the peridoic table
K.
Dmitri Mendeleev
The periodic table serves as an organizer for the elements. Not only does it group them by the amount of valence electrons they have (the vertical rows,) but it also groups them by having similar properties.
Metals in group 1 on peridoic table
Sr stands for strontium on the periodic table of elements.
Mardelev was the scientist who was the first person to discorver or invent the peridoic table!
Pelopium