The elements in which electrons are progressively filled in 4f-orbital are called lanthanoids.
There are 15 metallic chemical elements called lanthanoids.
Those elements are with atomic numbers from 57 to 71.
Lanthanoids belong to f-block elements because of the filling of the 4f-orbitals.
One of the lanthanoids, lutetium (chemical symbol Lu) has 14 electrons if 4f orbitals.
Electron configuration of lutetium: [Xe] 4f14 5d1 6s2
f-orbitals are similar to the d orbital, but cut in half (eight lobes instead of four).
Lanthanoids are used not as materials in catalysts, alloys, lasers and cathode-ray tubes.
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Answer:
Explanation:
yes leon is correct because matter is anything that takes space and also has mass in it.
thks.
Protons and neutrons are in the center of the atom, making up the nucleus. The charge on the proton and electron are exactly the same size but opposite. Neutrons have no charge.
Answer : Option B) Lead
Explanation : Lead is chemical element which damages<span> the central nervous system, cardiovascular system, reproductive system, hematological system, and kidneys with overexposure as compared to other elements in the given option.</span>