Mendeleev

-Mendeleev organised the periodic table by arranging each element into rows using the increasing of the atomic weight and the elements that had similar chemical properties were grouped in the same column.

-Mendeleev also used cards with element properties and moved them around until a pattern emerged. He kept some spaces blank on the table to show that his table was a law of nature, not just some random list.

Mendeleev organised the periodic table through arranging each element into rows by increasing atomic weight while each of the elements that had very similar chemical properties were grouped into the same column. Mendeleev also used cards with the element properties and moved them around like a puzzle until a pattern emerged. The significant of leaving some blank spaces was to show that his table was a law of nature, not just some random list and stated that there are still many undiscovered elements that existed that could possibly fill in those gaps. Dmitri Mendeleev | Biography, Periodic Table, & Facts | Britannica, Dmitri Mendeleev - Wikipedia

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-Mendeleev made predictions through looking at the blank spaces in his table using surrounding elements to estimate the properties of the missing ones.

-Mendeleev predicted Germanium by predicting its atomic weight, chemical formula, colours and reactivity with acids by looking at the gaps under silicon and above tin.

-In 1886, the German chemist, Clemens Winkler discovered germanium. Almost all the properties met Mendeleev’s predictions, which proved that his table was correct.

Mendeleev made predictions about elements that weren’t discovered yet through looking at the blank spaces in his table, using surrounding elements to estimate the properties of the missing ones, and used the prefix, “eka” for other elements. But how did he predict Germanium? Well he found the gap directly under silicon and above tin in Group 4 then predicted its atomic weight, chemical formula, colour and reactivity with acids. In 1886, The German chemist, Clemens Winkler discovered the new element and named it Germanium. All the properties met Mendeleev’s predictions almost exactly and this proved that his table was correct and convinced the scientific community.