The first attempt to classify elements was made by-

Correct option is A

The correct answer is (a) Dobereiner.
· Johann Wolfgang Döbereiner made the first known attempt to classify elements in the early 19th century. He introduced the concept of triads in 1829, grouping elements with similar properties into sets of three, known as "Döbereiner's Triads." He observed that the atomic weight of the middle element in each triad was approximately the average of the other two.
Information Booster:
· Döbereiner's Triads: An early classification, Döbereiner grouped elements like lithium, sodium, and potassium as a triad due to their similar properties and a relationship in atomic weights.
· Limitations: Döbereiner's triads could not classify all known elements and thus had limited applicability.
· Development in Classification: After Döbereiner, other scientists like Newlands (Law of Octaves), Mendeleev, and Meyer made significant advancements in the periodic classification of elements.
· Mendeleev’s Contribution: Mendeleev's periodic table, introduced in 1869, marked a breakthrough by arranging elements by atomic weight and predicting properties of undiscovered elements.