Dmitry Who? - Task 1
It’s All elemental v3 Worksheet
1. Why was it necessary to create a periodic table? Chemists needed a
way to organize the elements
2. What two properties are the modern periodic table based upon?
Atomic number and electron configuration.
3. Name the two men credited with the development of the first
periodic tables in 1869? Dmitri Mendeleev and Julius Meyer.
4. Mendeleev’s table was based upon atomic weight.
5. The table is called the periodic table because the elements have
similar properties and occur periodically.
6. Mendeleev’s periodic law states that the chemical and physical
properties of the elements vary in a periodic way with atomic weights.
7. The modern periodic law states that the properties vary with atomic
number not atomic weight.
8. Mendeleev’s table was arranged in rows, called periods, and columns
called groups. Elements of each group had similar properties.
9. Why didn’t some elements match perfectly on Mendeleev’s table? Because
his table was based on the atomic weights of the elements
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10. For this site, write the contribution of each person toward the
development of the Periodic Table of Elements.
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Greek thinkers used the words element and atom to describe the
differences and smallest parts of matter.
Lavoisier divided the few elements known in the 1700’s into 4 classes
John Dalton made the concept of atoms more convincing, suggesting
that the mass of an atom was it’s most important property
DeChancourtois made a cylindrical table of elements to display the
periodic re-occurrence of properties
Cannizaro determined the atomic weights for the 60 or so elements
known in the 1860’s.
Newlands arranged a table with elements given a serial number in
order of their atomic weights.
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Meyer constructed a periodic table, impressed by the periodicity of
physical properties.
Mendeleyev constructed a periodic table designed around chemical
properties
Mosely reordered the periodic table according to atomic numbers (
nuclear charge) rather than by weight.
Seaborg pulled out the heaviest elements, naming them the Actinide
series, permitting the placement of subsequent elements
Alexander arranged the periodic table according to atomic numbers
while retaining all accepted properties.
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11. When and where was Dmitry Mendeleyev born? Feb 8, 1834 Roblosk,
Siberia, Russia
12. How many children were in his family? 17 What place is he in the birth
order?17
13. Who influenced Mendeleyev's work considerably while at the Karlsruhe
Conference in Heidelberg, and how? Stanislao Cannizzaro, on the distinction
between molecular and atomic weight.
14. What were the two main themes that Mendeleyev developed while writing
his text book, The Principles of Chemistry? Relationships between the
properties and the element, lack of permanent position
15. Why did Mendeleyev leave gaps in his periodic table? And, were his
predictions correct? He thoufht that there would be more elements still
undiscovered. Yes.
16. Mendeleyev was aware of the necessity to use science to solve the
problems of the world. List four ways that Mendeleyev helped his country,
Russia. Improved the yield on crops, urged Russia t0 develop it’s own oil for
profit, improved Russia soda industry, and improved general agriculture.
17. What official position did Mendeleyev hold until his death in 1907? He
headed the Bureau of Weights and Measures.