Question

what is the first atempt of classification of elements . (I) metals and non metals or (2)dobereiners traids​

Answer 1

Answer:

1. Newland’s Law of Octaves

Will you believe that chemistry and music have a connection? That’s right. An English scientist by the name of John Newlands tried to classify the elements in a unique manner. He first started by arranging all the elements in a ascending order according to their atomic weights. Hydrogen being the lightest was obviously first. And at that time only 56 elements were known, the last one being thorium.

After arranging the elements so, Newland discovered that the first and the eight elements showed similar properties and characteristics. He compared this to the eight octaves of music (do, re, mi, fa, sol, la, ti) where every eight note is similar to the first. Hence this classification came to be known as Newland’s Law of Octaves.

However, there were a number of faults with the classification. To begin with, the law was only applicable up till Calcium. After calcium, every eighth element did not share similar properties to the first one. Also as new elements were discovered and the number expanded from 56, they did not fit into the law. Newland had also adjusted two elements into one slot and paired together some very unlike elements in order to make the classification work. Ultimately this classification also failed to leave a lasting impression.

2. Dobereiners traids

Dobereiner's law of triads states that, the atomic mass of the middle element of a triad is the arithmetic mean of the atomic masses of the other two elements. Example:In the triad of lithium, sodium and potassium.

Answer 2

Answer:

Metals,Metalloids and Nonmetals ..,... Nonmetals are usually poor conductors of heat and electricity, and are not mellable and ductile; many of the elemental non metals are gases at room temperature, while others are liquids and other solids .The metalloids are intermediate in their properties

2) Dobereiner's Classification:law of Traids In 1817 ,German chemist Johann dobereginer classified elements having similar chemical properties into groups of three These groups were called traids He proposed a law known as Dobereiner's law of traids

Explanation:

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