Cadmium

Cadmium is atom number 48 — every Cadmium atom has exactly 48 protons in its center, and that number is what makes it Cadmium and nothing else. Its symbol is Cd. At room temperature it is a solid.

Cadmium is a chemical element with symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it prefers oxidation state +2 in most of its compounds and like mercury it shows a low melting point compared to transition metals.

Summary from the source dataset, derived from Wikipedia (CC BY-SA 3.0) · original article

Cadmium sits in period 5, group 12 of the d-block. Its 48 electrons fill shells of 2, 8, 18, 18, 2 — written as [Kr] 4d10 5s2. Its electronegativity is 1.69 on the Pauling scale, and pulling the first electron off takes 867.8 kJ/mol. The outermost shell holds 2 electrons — the ones that do all the chemistry.

Full configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10
Ionization energies (kJ/mol): 867.8, 1631.4, 3616
Electron affinity: -68 kJ/mol · Electronegativity (Pauling): 1.69
Density: 8.65 g/cm³ · melts 594.22 K · boils 1040 K

Values exactly as published — see where the data comes from.