Jizzax politexnika instituti akademik litseyi

Homework: Ex-4: Retell the text;

Ex-5: Writing an essay: Water in our life;

Lesson – 15 Text: D.I.Mendeleev; Doing exercises;

Reading

Ex – 1: Read the text and discuss it;

D.I.Mendeleev, the great Russian scientist was born in Tobolsk, in 1834. After finishing the school, at the age of 16, he went Sankt Petersburg and entered the Pedagogical Institute. He graduated from the Institute in 1855. In 1866 D.I.Mendeleev was appointed professor at the University, where he gave a course of lectures on chemistry.

Interesting experiments were made in his classes both he and his students-assistants worked long hours in preparing the demonstrations so that all would go well.

At the University D.I.Mendeleev taught classes in the morning. In the afternoon he made experiments in his two room laboratory. At night D.I.Mendeleev spent much of his time working with the cards on which he put down information about each of the chemical elements.

D.I.Mendeleev made thousands of experiments with his own hands. He made thousands of calculations, wrote a lot of letters and studied many reports. Everything in the world that was known about the chemical elements D.I.Mendeleev knew.

For months, for years he searched for missing data. All those data were being brought together and groupped in a special way. In 1869 the description of more than 60 elements was completed and D.I.Mendeleev published his Periodic Table.

The Periodic Table is spoken of as beginning of a new era in chemical thought. D.I.Mendeleev was elected member of many academies of abroad. He died in 1909 at the age of 75.