Dmitri Mendeleev: The Creation Of The Periodic Table?

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Introduction: Dmitri Mendeleev is accredited with the creation of the periodic table but in reality, many scientists have contributed in the years leading up to the production. Before people could even write they knew some of the elements that are on the periodic table. The elements include silver, gold, copper, tin, lead, and mercury (substances that could not be broken down chemically). Not until 1649 did a man by the name of Hennig Brand discover phosphorous (an element) through scientific experiments and research. Another scientist, Johann Dobereiner, had begun to group elements with properties alike in the years of 1817 to 1829. He grouped elements into threes, or triads, and noticed that those with similar atomic weights …show more content…
Electronegativity is a chemical property of an element that refers to the atom’s capacity of binding and attracting electrons. Electronegativity increases left to right across a period (row) on the periodic table and decreases from top to bottom in a group on the table with the exceptions of noble gases, actinides, lanthanides, and transition metals for their lack of attracting electrons. Ionization energy refers to the energy needed to take away an electron from a neutral atom in a gas phase (Periodic Trends, n.d.). Ionization energy increases in a period left to right and decreases in a group from top to bottom. The capacity of an atom to accept an electron is called electron affinity. It increases left to right within a period and decreases top to bottom within a group. The atomic radius is half the area between two atoms’ nuclei. It increases top to bottom in a group and decreases left to right. The melting point of an element is the energy required to change the substance from a solid to a liquid. Finally, an element’s metallic character can be referred to as how easily an electron can be lost by an …show more content…
Graph paper and a pencil were used to sketch out what the lines and bars would look like in each graph with its different variables using my hypotheses. For graphs one and three (line graphs), the information on the Table S worksheet was used. For the other two graphs (bar graphs) the information on the Chemistry Lab worksheet were used. Line graphs were used to see the relationship between atomic number to atomic radius and atomic number to ionization energy since the numbers of atomic radius and ionization energy were so large. Bar graphs were used for graphs two (period number to atomic radius) and four (period number to ionization energy) because elements that had the same period number were placed side-by-side, making it less complicated to see the increase/decrease in either the ionization energy or atomic radius of the

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