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p-Block Elements: Part I (Group 13 & 14) formula sheet

Every formula in the p-Block Elements: Part I (Group 13 & 14) chapter for JEE Main, with one line on when it applies. Topic 1 is open to everyone; sign in free to read all 17 and download the PDF.

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Group 13: trends and oxidation states

Group 13 at a glance
11× asked, last 2025
BAlGaInTlr (pm)85143135167170r(MX3+)2753.5628088.5ΔiH1801577579558589ΔiH224271816197918201971m.p. (K)2453933303430576χ2.01.51.61.71.8\begin{array}{lccccc}&\text{B}&\text{Al}&\text{Ga}&\text{In}&\text{Tl}\\ r\ (\text{pm})&85&143&135&167&170\\ r(\ce{M^{3+}})&27&53.5&62&80&88.5\\ \Delta_iH_1&801&577&579&558&589\\ \Delta_iH_2&2427&1816&1979&1820&1971\\ \text{m.p. (K)}&2453&933&303&430&576\\ \chi&2.0&1.5&1.6&1.7&1.8\end{array}
ns2np1ns^2np^1; IE in kJ mol−1^{-1}. Ga < Al in radius (3d3d shields poorly). Ga: liquid from 303 to 2676 K.
Boron
5× asked, last 2024
4 B+3 OX2→Δ2 BX2OX3,2 B+NX2→Δ2 BN\ce{4B + 3O2 ->[\Delta] 2B2O3},\qquad \ce{2B + N2 ->[\Delta] 2BN}
Hard non-metal. No d orbitals: covalency stops at 4 ([BFX4]X−\ce{[BF4]-}); Al forms [AlFX6]X3−\ce{[AlF6]^{3-}}.
Inert pair effect
8× asked, last 2025
stability of +1: Al<Ga<In<TlE∘(AlX3+/Al)=−1.66 V,E∘(TlX3+/Tl)=+1.26 V\begin{aligned}&\text{stability of }+1:\ \text{Al}<\text{Ga}<\text{In}<\text{Tl}\\&E^\circ(\ce{Al^{3+}/Al})=-1.66\ \text{V},\qquad E^\circ(\ce{Tl^{3+}/Tl})=+1.26\ \text{V}\end{aligned}
B, Al: +3 only; Tl mainly +1, so TlX3+\ce{Tl^{3+}} is a strong oxidant. TlIX3\ce{TlI3} is TlX+ IX3X−\ce{Tl+ I3-}.
Trihalides
4× asked, last 2024
Lewis acidity: BFX3<BClX3<BBrX3<BIX3BFX3+NHX3→FX3B ⋅ NHX3,2 AlClX3→AlX2ClX6\begin{aligned}&\text{Lewis acidity: }\ce{BF3}<\ce{BCl3}<\ce{BBr3}<\ce{BI3}\\&\ce{BF3 + NH3 -> F3B*NH3},\qquad \ce{2AlCl3 -> Al2Cl6}\end{aligned}
Empty p orbital: Lewis acid. BFX3\ce{BF3} weakest: most back-bonding (2p–2p). AlX2ClX6\ce{Al2Cl6}: two bridging Cl, Al sp3sp^3.

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Practise p-Block Elements: Part I (Group 13 & 14)

13 more formulas in 5 topics

Boron compounds, Aluminium and alums, Group 14: trends and oxidation states, Carbon: allotropes and oxides and Silicon compounds. Read the first part free. Sign in free with Google to read the rest and download the PDF.

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Boron compounds

  • Borax and boric acid5×
  • Heating boric acid
  • Diborane and borazine6×

Aluminium and alums

  • Aluminium3×

Group 14: trends and oxidation states

  • Group 14 at a glance4×
  • Catenation3×
  • +2 versus +44×

Carbon: allotropes and oxides

  • Allotropes of carbon2×
  • Nature of the oxides7×
  • CO and CO₂

Silicon compounds

  • Silicones2×
  • SiCl₄ and SiO₂
  • Silicates

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Practise p-Block Elements: Part I (Group 13 & 14)

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