Any element in group 18 has eight valence electrons (except for helium, which has a total of just two electrons). Examples include neon (Ne), argon (Ar), and krypton (Kr). Oxygen, like all the other elements in group 16, has six valence electrons.
Friction <span>is most responsible for slowing a bicycle down when the brakes are applied</span>
Zn, Cd, and Ag are transition metals that usually form only one monoatomic cation.
A monatomic cation is a cation made of only one atom.
Cations are positively charged ions, in this example Ag⁺, Cd²⁺ and Zn²⁺.
These cations form only one type of ion, while iron and copper form more than one type of cations.
Iron and copper form cations with different charges (Fe²⁺, Fe³⁺, Cu⁺, Cu²⁺).
It depends on electron configuration which type would be formed.
Electron configuration of zinc atom: ₃₀Zn 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s²
Transition metals are elements in the d-block of the Periodic table.
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