Too much for a simple answer on WikiAnswers !
Please read an introductory treatise on inorganic chemistry.
i dk why asking me google it i am dumb
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Mass number is term used for isotopes, not for elements. And it is boring to list here all the isotopes of the first 20 elements.
HydrogenHeliumLithiumBerylliumBoronCarbonNitrogenOxygenFluorineNeonSodiumMagnesiumAluminumSiliconPhosphorousSulphurChlorineArgonPotassiumCalciumHope this helped :)
give me graph paper first!!!!!!!!!!!!!!
Yes that is true for the first 20 elements, except helium and hydrogen which needs 2 valance electrons to be complete. After 20, things change, but we don't need to worry about it at the basic level.
Period 1 (Elements 1 and 2)1s1 - 1s2Period 2 (Elements 3 - 10)2s1 - 2s22p6Period 3 (Elements 11 - 18)3s1 - 3s23p6Period 4 (Elements 19 and 20)4s1 - 4s2
The first twenty elements are made up f different things
H -->+1 He --> 0 Be --> B
Carbon (C) has the highest melting point out of all the elements, and so, as it's in the first 20 elements, it has the highest melting point of the first 20 elements too. Its melting point is 3823K.
Well i think that will be boron according to the first 20 elements.
Nitrogen = 3 unpaired electrons.