Iron

Iron is atom number 26 — every Iron atom has exactly 26 protons in its center, and that number is what makes it Iron and nothing else. Its symbol is Fe. At room temperature it is a solid.

Iron is a chemical element with symbol Fe (from Latin:ferrum) and atomic number 26. It is a metal in the first transition series. It is by mass the most common element on Earth, forming much of Earth's outer and inner core.

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

Iron sits in period 4, group 8 of the d-block. Its 26 electrons fill shells of 2, 8, 14, 2 — written as [Ar] 3d6 4s2. Its electronegativity is 1.83 on the Pauling scale, and pulling the first electron off takes 762.5 kJ/mol. The outermost shell holds 2 electrons — the ones that do all the chemistry.

Full configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d6
Ionization energies (kJ/mol): 762.5, 1561.9, 2957, 5290, 7240, 9560, 12060, 14580 … (26 published)
Electron affinity: 14.785 kJ/mol · Electronegativity (Pauling): 1.83
Density: 7.874 g/cm³ · melts 1811 K · boils 3134 K

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