Question 3: What were the drawbacks of Dobereiner’s triads? He based his work on previous discoveries made by scientists such as Antoine-Laurent de Lavoisier and John Newlands. Dmitri Mendeleev published the table in 1869. The periodic table has a history that spans over a century of progress in chemical property understanding. Question 2: Give a brief history of periodic classification of elements. As a result, in Mendeleev’s periodic table, they are grouped together in a separate group called zero groups. Noble gases such as helium (He), neon (Ne), argon (Ar), krypton (Kr), and xenon (Xe) are the most inert (non-reactive) of all known elements and are present in very low concentrations in our atmosphere. Question 1: Why are the Noble Gases Placed in a Separate Group? As a result, this method of classifying elements left no room for the discovery of new elements. Elements that were discovered later could not be incorporated into the octave pattern.

As a result, new elements could not be discovered using this classification scheme. The octave layout was unable to accommodate later discovered components.Elements with higher atomic masses had atomic masses that were too large to fit within octaves. Only up to calcium did Newland’s law of octaves hold true.Metals such as cobalt, nickel, and platinum, for example, were classified with halogens. Element qualities that were distinct were grouped together.Nickel and cobalt were both placed in the same slot. In Newland’s periodic classification, some elements were grouped together.Lithium, sodium, and potassium, for example, were combined. For the lighter sections, this method performed significantly better.The Newlands law of octave was the first to be based on atomic weight, linking element properties to atomic masses.

The statute gave the government extensive authority to organise all known elements into a tabular format.

This law establishes a framework for classifying items with comparable features into groups.

When elements are arranged in increasing atomic mass order, Newland’s law of octaves states that the properties of the eighth element are the same as the first.

The chemical properties of fluorine and chlorine are similar.

Chlorine is the eighth element after fluorine.

Potassium, lithium, sodium, and potassium are the chemical properties of the eight sodium elements.

Sodium is one of lithium’s eight elements.

However, this method of classifying elements was met with skepticism in the scientific community. This was the first time an atomic number was assigned to each element. Newlands contrasted the components’ proximity to musical octaves, in which every eighth note is comparable to the first. The law of octaves states that when the elements are arranged in ascending order of atomic mass, every eighth element has comparable properties. As a result of this discovery, Newland’s law of octaves was born. He arranged them in ascending order according to their atomic weights and discovered that the properties of every eighth element were the same. Newland’s Law of OctavesĪ British chemist named John Newlands attempted to combine the 62 elements known at the time in 1864. Li (6.9), Na (23), and K are only a few examples (39). The atomic mass of the triad’s middle element is almost equal to the average of the other two elements’ atomic masses. According to this, groups of three elements with comparable properties are formed when elements are stacked in order of increasing atomic masses. The atomic mass serves as the basis for this classification.

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