Since the very dawn of man’s understanding of the world we have sought to build up and break down the materials that we see around us. After the physical breaking down of rocks and plants man most likely burnt materials. This process can be partial or complete but when burning wood, in either case, often carbon would be left. Unknowingly then this was then the first elemental substance to be identified. Since then man has sought to categorise substances and some just cannot be isolated any further. We call these elements and it is only since trying to purify metals was any form of rigor applied to the subject.

This was the dawn of the science of chemistry. Slowly people realised that there were patterns to the way that elemental substances reacted with one-another. Starting in 1661, with Robert Boyle stating that elements are "those primitive and simple bodies of which the mixt ones are said to be composed and into which they are ultimately resolved”,  it took two further centuries of many different kinds of discoveries before John Newlands Law Of Chemical Octaves came in 1864 and finally Dmitry Mendeleyev proposed the Periodic Table in 1868.

The map was of course incomplete but it gave chemists a far better guide of where to look for the missing pieces to a jigsaw that these days we now take for granted. It was a major leap forward and is still the best way of using the overlapping subjects of physics and chemistry to explain the organic and inorganic world in which we live. The most common one are in this interactive table below -the gaps are not missing merely omitted for clarity here.

<< Fascinating Master Page

A much more detailed version can be found here:  Periodic Table

Li

Lithium

Na

Sodium

Rb

Rubidium

Cs

Caesium

Be

Berylium

Mg

Magnesium

Ca

Calcium

Sr

Strontium

Ba

Barium

Cr

Chromium

Mn

Manganese

Fe

Iron

Co

Cobalt

Ni

Nickel

Cu

Copper

Pa

Palladium

Pt

Platinum

Ag

Silver

Au

Gold

Zn

Zinc

Cd

Cadmium

Hg

Mercury

Al

Aluminium

Sn

Tin

Pb

Lead

B

Boron

Si

Silicon

Ge

Germanium

C

Carbon

N

Nitrogen

P

Phosphorus

O

Oxygen

S

Sulphur

F

Flourine

Cl

Chlorine

Br

Bromine

I

Iodine

He

Helium

Ne

Neon

Ar

Argon

History

The history of chemical discovery is an amazing story in itself. Wikipedia have done an excellent job:  History Of The Periodic Table

Fascinating Chemical Facts

Some of the elements named above are highlighted in blue. These link to fascinating stories often more than just the history of the substance named.

(There are only a few at present. They are good and more will be added as time goes on so do come back and check the Last Update date at the top right)

Detailed Data

Extremely detailed data on all elements, including physical/electronic properties, etymology and history:

See:                             Chemicool

Plus energy levels:   PTable.com

But for a really superb rundown on the properties of every single element see the periodic table at Royal Society of Chemistry. Hover over for a quick glacnce or click to go to a full webpage. At the top, in rather small writing you can move forward and back (by Atomic Number). On each page there is a link to ChemSpider -click the Articles tab and you will find a list of links and abstracts about the isotopes and uses of that element. The list can be long in some circumstances.

Goto: Interactive Periodic Table: Royal Society of Chemistry

Colour In Our World

Most mammals see our world in colour. That colour is there both naturally and by biological means. This is a superb website with a search function. Particularly fascinating is the study of Chlorophyl.

    WebExhibits: Causes Of Colour

Further Information

Scroll down on the Fascinating Biology page to:  What Animals See In Colour Or At Night

Flame Tests

If atoms are made more excited, usually by heating but it can be useful in electronics eg TVs, when the atom drops back into its unexcited state nanoseconds later it releases its energy dependent on the size of the gap between energy levels which is fixed per element. Quite a few elements do this in the visible spectrum. These colours can be seen by exposing a compound, containing the following metals, to the extremes of heat in a suitable flame eg bunsen burner. The the colours seen are shown..

Note this electronic Spectroscopy of quite different to physical Chromatography.

A-Level Help

The following file was part of the British A-Level syllabus. It starts off easy and works up to the best explanations and examples that I’ve ever seen (2Mb download):     AcidAndBaseTheoryComplete_AdvancedLevel.pdf.

I don’t like this website anymore. I used to be well laid out but it isn’t anymore. However it does give useful explanations:  LibreTexts: Overview of Acids & Bases

Strengths relative to pure water.

Three Types

There are three main types of bonding. This triangle uses the extremes of Lithium and Flourine to illustrate the relative strengths of bonding in simple compounds.

Be aware that this does not cover all elemental self bonding, that of large molecules and temporary biological processes. These are covered here (0.8Mb download):

AtomicBonding_AdvancedLevel.pdf

GCSE Help

In metals electrons are completely free of their parent atoms. Bonding occurs within this sea and thus metals have many useful properties like malleability, electron conduction etc.

Covalent and Ionic bonding involves the restricted sharing of electrons -but rarely equally.

Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons.

Periodic table showing relative Electronegativity (Pauling Scale).

The implication of all this is that there is no clear-cut division between covalent and ionic bonds. In a pure covalent bond the electrons are held on average exactly half way between the atoms. In a polar bond the electrons have been dragged slightly towards one end.

How far does this dragging have to go before the bond counts as ionic? Whilst there is no real answer normally  sodium chloride is considered as being a typically ionic solid. However even here the sodium hasn't completely lost control of its electron. Because of the properties of sodium chloride we tend to count it as if it were purely ionic.

See here for more:  ChemGuide: Electronegativity

This is my very favourite area of chemistry but it’s not for everyone so I merely append a chart of modern naming conventions here. As I said on the Need A Website To.. page the Khan Accademy gives free courses on a wide range of subjects. For help you could do worse than to see the free short video tutorials and discussions available here: Khan Accademy: Organic Chemistry