Lanthanum, with the chemical symbol La, is the chemical element with the atomic number 57.
The atomic number of the element lanthanum on the periodic table is 57.
Lanthanum's atomic number is 57 thus it has 57 protons, the number of protons an atom has is equal to the atomic weight, in this case 141 minus the number of protons or 57 so, 141-57=84 Lanthanum-141 has 84 neutrons.
Lanthanum has 57 protons and 81-82 neutrons.
Technetium (atomic number 43) is the inner transition metal with the lowest atomic number.
Lanthanum See Related Link
It is a metal with the symbol La its atomic number is 57. Its color is silver white.
187 picometers.
The noble gas configuration for Lanthanum is [Xe] 5d1 6s2. Lanthanum has 57 electrons, so the noble gas before it (Xenon - atomic number 54) has a configuration of [Xe].
The lantanides (6f-block elements) start, after 57Lantanium, with atom number 58, Ce, to end with 71Lu
The oxidation number for lanthanum is +3.
Im not sure about the atomic mass bit but Lanthanum is a silvery white, malleable, ductile, and soft rare-earth metal xx
138.90547 amu