Doc Brown's Chemistry Clinic

 The Periodic Table

Part 11 DATA on selected Groups & Series of Elements

 Advanced Level Inorganic Chemistry Revision notes

(e.g. UK Advanced Level Chemistry GCE-AS-A2-IB US K12 grades ~11-12)

Part 11 Data page sub-index * 11.1 Notes on the data * 11.2 Periodicity data-graphs * 11.3 Group 1 Alkali Metals * 11.4 Group 2 Alkaline Earth Metals * 11.5 Transition Metals * 11.6 Group 3(13) * 11.7 Group 4(14) * 11.8 Group 5(15) * 11.9 Group 6(16) * 11.10 Group 7(17) Halogens * 11.11 Group 0(18) Noble Gases * 11.12 Full Periodic Table *  EMAIL query?comment

Advanced Periodic Table Index * Part 1 A brief Periodic Table history * the modern Periodic Table * Part 2 Electronic structure of atoms : Spectroscopy and the H spectrum * Part 3 Period 1 survey : 1. Hydrogen : 2. Helium : Summary of  Period 1 : heavier element formation-stellar nuclear fusion * Part 7 s-block metals Groups 1/2 Alkali/alkaline Earth Metals * Part 10 3d-block Sc-Zn and Transition Metals *

Alphabetical Element name list with symbol and atomic number (Z)

11.1 Some Notes on the Data presented

I cannot offer 100% authenticity on the data, values vary from source to source, but I've done my best to sift the sources!

na means not applicable or not available.

sub means it sublimes (solid ==> gas) on heating.

Allotropes are different physical forms of the same element in the same physical state (examples).

To convert melting/boiling points to Kelvin, add 273 (K = ^oC +273)

To convert density to kgm^-3, multiply by 1000 (kgm^-3 = gcm^-3 x 1000)

IE = ionisation energy, it is the energy required to remove the most loosely bound electron from a gaseous atom or positive ion (it is always endothermic) e.g.

1st IE of helium, He_(g) ==> He⁺_(g) + e^-, H = +2370kJmol^-1 

2nd IE of sodium, Na⁺_(g) ==> Na²⁺_(g) + e^-, H = +4562kJmol^-1 

Atomic or ionic radii are quoted in pm = picometre = 10^-12m,

to convert to nm = nanometre = 10^-9m, divide pm by 1000 (or pm = nm x 1000).

These radii can be considered as the boundary within the electrons spend the majority of their time (sometimes quoted as 95% of all electron charge).

There are some general rules on radii:

Positive ion (cation) radii are always smaller than atomic radii because the same positive nuclear charge is attracting and holding less electrons. The more electrons removed, the smaller the radius becomes.

Negative ion (anion) radii are always larger than atomic radii because the same positive nuclear charge has to attract and hold more electrons. The more electrons added, the larger the radius becomes.

So in general, for radii, ignoring other factors: ... X^2- > X^- > X > X⁺ > X²⁺ ... etc.

Electronegativity is the electron attracting power of an atom in a covalent bonding situation (the Pauling scale is used here). The lowest values occur with the most reactive metals with the lowest IE's at the lower left of the periodic table. The highest values occur with the most reactive non-metals with the highest IE's at the upper right of the periodic table.

The electron configurations are quoted twice, (i) by the number of electrons in each principal shell, (ii) using the more advanced modern s, p, d and f sub-shell notation.

The oxidation states quoted, are those most likely to be encountered, but their relative stability is variable and important. In the detailed notes I will point out their relative importance. Detailed notes on oxidation state and redox reaction theory.

The electrode potentials (half-cell E values), apart from groups 1 and 2, usually refer to aqueous systems with a pH of 7 or less. Particularly for transition metals, the half-cell values can significantly change from acid to alkaline media, another data problem!

Electron Affinity is the energy change associated with a gaseous atom or negative ion gaining an electron e.g.

for the electron affinity of chlorine: Cl_(g) + e^- ==> Cl^-_(g), H = -364kJmol^-1 

Bond energy (bond enthalpy) is the energy required to break one mole of a particular bond from a species in its gaseous state (at 298K, 1 atm.). Most values are a typical or average values for gaseous species.

for the hydrogen chloride bond energy: HCl_(g) ==> H^._(g) + Cl^._(g), H = +431kJmol^-1 

Flame colours have been included for some s-block metals as they are used as simple identity tests (the transition metal copper gives a green flame colour, and some blue)

11.2 Three selected PERIODICITY data-graphs

These graphs have been added covering Periods 1-6 and the start of Period 7 to help in the study of 'Periodicity'. They present data tables and graphs of melting/boiling point, 1st ionisation energy, atomic radius and Pauling electronegativity. Links to the first 'experimental' editions below.

Elements 1-20 covering Periods 1-3 and start of Period 4

Elements 1-38 covering Periods 1-4 and start of Period 5

Elements 1-96 covering Periods 1-6 and start of Period 7

and six extra periodic table data links if needed