Talk:Tetrahedral molecular geometry

the Periodic Table is sliced up tetrahedron[edit]

The tetrahedron is very special geometric shape in chemistry. The Periodic Table has four major areas that are called s,f,d,p blocks. It was recently discovered that those blocks, if ordered and proportioned in accordance with the quantum numbers, are simply the slices of regular tetrahedron. You can check it out at ADOMAH Periodic Table Web site. -Drova (talk) 13:22, 19 February 2009 (UTC)[reply]

Irrelevant to this article. AGAIN. — Arthur Rubin (talk) 14:14, 3 March 2009 (UTC)[reply]

Number of sig figs for the bond angle[edit]

Do we really need so many significant figures in cos⁻¹(−1⁄3) = 109.4712206...° ≈ 109.5°? Joel Brennan (talk) 14:19, 16 June 2021 (UTC)[reply]

I think it is acceptable to state the value of the angle to many figures ONCE, since the object of an encyclopedia is to give information accurately. Of course after the first time, the remaining mentions of the angle are rounded off to 1 or 2 figures after the decimal point.

Note also that the figures are correct and therefore really significant, since the calculation is mathematical and not based on any measurement. Dirac66 (talk) 01:18, 28 June 2021 (UTC)[reply]