• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

A History of the Periodic Table.

Extracts from this document...


A HISTORY OF THE PERIODIC TABLE Introduction D�bereiners Triads In the early 1800s Dobereiner noted that many of the known elements could be arranged in triads - a group of 3 chemically similar elements. Two of these triads are Chlorine, Bromine, Iodine and Lithium, Sodium Potassium. D�bereiner's Triads Ca 40.1 Sr 87.6 Ba 137.3 S 32.1 Se 79.0 Te 127.6 Cl 35.5 Br 79.9 I 126.9 He showed that when the three elements in each triad were arranged in order of Relative Atomic Mass, the middle element had properties intermediate to those of the other two elements. Also the Relative Atomic Mass of the middle element was close to the mean Relative atomic Masses of the other two elements. ...read more.


Newlands' Octaves H Li Ga B C N O F Na Mg Al Si P S Cl K Ca Cr Ti Mn Fe Co,Ni Cu Zn Y In As Se Br Rb Sr Ce,La Zr Di,Mo Ro,Ru Pd Ag Cd U Sn Sb Te I Cs Ba,V Ta W Nb Au Pt,Ir Tl Pb Th Hg Bi Cs Newlands Octaves: The eighth element is a kind of repetition of the first like the eighth note of an octave in music. His work wasn't very well received by the scientific community because there weren't any empty spaces his table which assumed that all the elements had been discovered even though 4 elements had been discovered a few years before his work was published so the discovery of a new element could throw the idea out of the window. ...read more.


The peaks had alkali metals: sodium, potassium, rubidium, and caesium. Each fall and rise to a peak, corresponded to a period like the waves. In each period a number of physical properties other than atomic volume also fell and rose, such as valence and melting point. Figure below shows the curve obtained by Lothar Meyer when he plotted the atomic masses and the respective atomic volumes. Each peak started with a new period. Note the graph shows the inert gases which were discovered later in 1894 by William Ramsey. These elements represented a new group. Dimitri Mendeleev The most famous work that was done in developing the periodic table was done by a Russian chemist, Dmitri Mendeleev. Mendeleev developed his periodic table in 1869. It was a table, not a graph. http://home.att.net/~cat6a/class_elem-III.htm http://dl.clackamas.cc.or.us/ch104-07/mendeleev_3.htm Mohammed Seedat 1 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Classifying Materials section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Classifying Materials essays

  1. Marked by a teacher

    Chemistry Revision Notes on atomic structure, nuclear power and the periodic table

    4 star(s)

    Elements in the same groups will have the same valency where it is the atoms in the same group that will likely have the same chemical properties. These are labelled in several ways but most commonly either by Roman Numerals from I to VIII or from 1A to 8A/0.

  2. Marked by a teacher

    The History of the Periodic Table

    4 star(s)

    After doing so, he was able to predict the properties of a new element using the properties of the other elements in that group. Now, the elements are arranged in order of increasing atomic number. This Periodic Table was improved again in 1895 when a completely new group was introduced for the noble gases as previously none had been discovered.

  1. Peer reviewed

    Revision notes on elements, the periodic table and compounds.

    4 star(s)

    Properties of a compound is different from the properties of its constituent elements. 3. A compound can only be broken down into simpler substances by chemical methods Can use the following methods: - Heating (but compounds NOT ALWAYS change to its components when heating)

  2. Free essay

    Periodic table

    - The valency of an element is equal to the number of electrons that atom needs to gain, lose or share to fill its outer shell. If electrons are lost the valency it + and if electrons are gained the valency is -.

  1. A practical study of the periodic table.

    The chlorides The chlorides of sodium and magnesium dissolve in water without any chemical reaction. They give solutions in which their component ions behave independently. The bonds that occur in those chlorides are ionic. NaCl(s) + H2O(l) � Na+(aq) + Cl-(aq)

  2. The role of mass customization and postponement in global logistics

    This means to postpone changes in inventory location downstream in the supply chain to the latest possible point. In the key work by Zinn and Bowersox, five different types of postponement strategies are identified. Four different strategies of form postponement (labeling, packaging, assembly and manufacturing)

  1. The relative atomic mass of lithium

    100*0.002818/25= 6.21 Error calculations: 6.2*100/7= 88.57 ---- which means that there is 11.43 % error in the second method Conclusion: After finishing the experiment, I came to the conclusion that that the value calculated, for the first method was more accurate than the value for the second one.

  2. Determination of the relative atomic mass of lithium

    Repeat the titration consistent result. Show all your result 5. Record the overall titre. TABLES OF RESULTS& CALCULATINF THE RAM OF LITHIUM. 1. For volume TRIES VOLUME BEFORE (cm3) VOLUME USED (H2 in cm3) WEIGHT OF LITHIUM 1st TRY 250 181 0.1g 2st TRY 250 175 0.1g 3rd TRY

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work