Put the sentences into Present Perfect Continuous, make negative sentences and questions. 1. He (play) at the school sport ground for 2 hours. (How long?) 2. They (go) shopping in the mall for 3 hours. (Where?) 3. I (read) a magazine in my room for half an hour. (What?) 4. I (sing) in the classroom for 10 minutes. (Where?) 5. She (swim) in the pool for 20 minutes. (How long?) 6. We (make) a snowma
Dmitri Ivanovich Mendeleev was born on 8 February 1834 near Tobolsk. He was a Russian inventor and chemist. The most famous invention of Mendeleev is periodic table of elements.
Early life
Mendeleev’s parents were Maria Mendeleeva (nee Kornilieva) and Ivan Mendeleev. According to the different sources there were approximately seventeen children in their family. Mendeleev was the youngest child. His father worked as a teacher but he became blind and stopped working. As a result Maria Mendeleeva began to work and re-established the glass factory which belonged to her family. It is also known that Mendeleev’s grandfather was a priest of the Russian Orthodox Church. When Mendeleev was 13 he entered the Gymnasium in Tobolsk.
In 1849 his family moved to Saint Petersburg. In 1850 Mendeleev joined The Main Pedagogical Institute. Following the graduation he developed tuberculosis and was forced to relocate to the Crimean Peninsula. Living there, Mendeleev became a science master of the Simferopol gymnasium #1. In 1857 after recovery he arrived in Saint Petersburg.
Later life
From 1859 to 1861 Mendeleev worked in Heidelberg and researched the capillarity of liquids. In April 1862 he married Feozva Nikitichna Leshcheva. Two years later Mendeleev became a professor at the Saint Petersburg Technological Institute. In 1865 he became a professor at Saint Petersburg State University. The same year Mendeleev completed his dissertation "On the Combinations of Water with Alcohol". By 1871 Saint Petersburg was known as a center for chemistry research. In 1876 Mendeleev fell in love with Anna Ivanova Popova. In 1881 he made a proposal of marriage to her. The following year Mendeleev married her. The same year he divorced his first wife. Mendeleev had two children from his first marriage: Olga and Vladimir. His other children from the second marriage were Lyubov, a pair of twins and son Ivan. It should be noted that Lyubov was the wife of Russian poet Alexander Blok.
Mendeleev obtained a lot of awards from different scientific organizations but he resigned from Saint Petersburg University in 1890. Three years later Mendeleev was appointed Director of the Bureau of Weights and Measures. His task was to formulate new standards of vodka. According to the new standards created by Mendeleev all vodka had to be made at forty percent alcohol by volume. He also researched the composition of petroleum and made a contribution to the foundation of the first Russian oil refinery.
In 1906 the Nobel Committee for Chemistry suggested to the Swedish Academy to award the Nobel Prize in Chemistry for 1906 to Mendeleev for his discovery of the periodic system. This proposal was approved. But at the full meeting of the Academy one of the members recommended the candidacy of Henri Moissan. Moreover Svante Arrhenius who had influence on the Academy also advised to reject the candidacy of Mendeleev. The contemporaries state that Arrhenius was against Mendeleev because of his critique of Arrhenius's dissociation theory. As a result the candidacy of Mendeleev was rejected.
Dmitri Mendeleev died of influenza in Saint Petersburg in 1907