History of the Periodic Table
Antoine-Laurent Lavoisier
In France, in the late 1700s, Antoine-Laurent Lavoisier conducted work that would revolutionize the science of chemistry. He is known as the father of modern chemistry. Antoine Lavoisier helped change the way scientists observed chemistry to scientists conducting and measuring experiments in the way that it is today. Lavoisier designed a balance that could measure object’s mass to the nearest 0.0005 gram to help him provide an example of making careful measurements. Lavoisier conducted many experiments to show how chemical compounds form by determining the composition of the compounds used in his experiments. The more compounds Lavoisier discovered, the harder it became to memorize their different names. Lavoisier then began to work with other chemists to develop a method for naming new compounds. They were able to write the first list of elements containing 33 elements that were distinguished between metals and non-metals.
John Newlands
In 1864, an English chemist named John Newlands was working on the periodic table. Newlands took the elements from the periodic table and classified them in order of their atomic mass. Afterwards, Newlands noticed similarities between every eighth element on the periodic table he created which resulted in his Law of Octaves.
Lothar Meyer
In 1864, a German chemist named Lothar Meyer created a periodic
table based on 28 elements which were listed by their valence. Later in 1870, Meyer published a paper that differed from his last periodic table. Inside the paper, he had created a graph relating atomic volume and atomic number. He also compared the relation between the properties of elements and their atomic weights. However, that same year another chemist named Dmitri Mendeleev published his table of the elements before Meyer. Mendeleev was given more credit than Meyer for his periodic table because it was published first and he was able to explain its efficacy.
table based on 28 elements which were listed by their valence. Later in 1870, Meyer published a paper that differed from his last periodic table. Inside the paper, he had created a graph relating atomic volume and atomic number. He also compared the relation between the properties of elements and their atomic weights. However, that same year another chemist named Dmitri Mendeleev published his table of the elements before Meyer. Mendeleev was given more credit than Meyer for his periodic table because it was published first and he was able to explain its efficacy.
Dmitri Mendeleev
In 1869, a Russian chemist named Dmitri Mendeleev rearranged the elements of the periodic table into vertical columns according to similar characteristics he noticed between them. He placed the similar elements under each other and left gaps for future elements that had yet to be discovered. Mendeleev had developed the original periodic table based on the atomic masses of the elements. Mendeleev predicated the chemical properties of these unknown elements for which he left gaps. When these elements were discovered, Mendeleev's predictions were very close to the exact properties. The relatively accurate predictions helped persuade scientists that Mendeleev’s periodic table was a useful tool.
Henry Moseley
In 1914, an English physicist names Henry Moseley developed an
x-ray spectroscopy to study atomic structures. He measured the wavelengths of multiple elements using the x-ray. His results showed that the ordering of the wavelengths and the ordering of the elements by atomic number corresponded. He realized that elements varied by atomic number and not by atomic weight, which Mendeleev had hypothesized. Moseley reconstructed the periodic table by elements
arranged in order of their increasing atomic umber. Henry Moseley had created the modern periodic table.
x-ray spectroscopy to study atomic structures. He measured the wavelengths of multiple elements using the x-ray. His results showed that the ordering of the wavelengths and the ordering of the elements by atomic number corresponded. He realized that elements varied by atomic number and not by atomic weight, which Mendeleev had hypothesized. Moseley reconstructed the periodic table by elements
arranged in order of their increasing atomic umber. Henry Moseley had created the modern periodic table.