# data[].attributes.body
Dmitri Ivanovich Mendeleyev was a Russian chemist, best known for his discovery of the underlying pattern and publication in 1869 of the first version of the periodic table, now known as the periodic table of the elements. He also did research that led to the enunciation of the periodic law of the elements, the basis of the periodic system that bears his name. He was influenced by the 1858 article ‘Sunto di un corso di Filosofia Chimica’ by Stanislao Cannizzaro. In 1869 he published his book Principles of Chemistry, in which he developed the theory of the periodic table.

# data[].attributes.body
Dmitri Ivanovich Mendeleyev was a Russian chemist, best known for discovering the underlying pattern and publishing in 1869 the first version of the periodic table, now known as the periodic table of the elements. He was born in the village of Verkhnie Aremzyani, located east of Tobolsk, Siberia. He was the youngest of 17 childrens living in a family with his mother and father.

# data[].attributes.attachment_link.title
Qué es la teoría de la relatividad de Einstein y por qué fue tan revolucionaria

# data[].attributes.body
In 1869, Mendeleïev, a Russian chemist, presented a first version of his periodic table in 1869. This table was the first coherent presentation of the similarities of the elements. He realised that by classifying the elements according to their atomic masses, a periodicity appeared with regard to certain properties of the elements. The first table contained 63 elements.

# data[].attributes.body
The atom is the fundamental unit of the chemical elements. It consists of a nucleus containing positively charged protons and uncharged neutrons. Every solid, liquid, gas and plasma is composed of neutral or ionised atoms. Atoms are microscopic; typical sizes are around 100 pm.