Element 49

Indium (In)

49

In

indium

Metal · p block · group 13, period 5

Electron configuration: $[\mathrm{Kr}]\,5s^{2}\,4d^{10}\,5p^{1}$
Unpaired electrons: 1 (paramagnetic)
Valence electrons: 3
Molar mass: 114.82 g/mol
Electronegativity: 1.78
Atomic radius: 167 pm
First ionization energy: 558 kJ/mol
Next ionization energies: 1,821, 2,704, 5,210
Electron affinity: 29 kJ/mol released

Practice

Practice indium

Questions from the course about indium. If you’re signed in, your answers count toward your progress.

Question 1Compare two elements and explainExam level
Which element has the higher first ionization energy, $\ce{In}$ or $\ce{Sn}$ , and why?

Where it comes up in the course