Margaret Todd (doctor)
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Margaret Georgina Todd was a Scottish medical doctor and writer. She coined the term isotope in 1913 in a suggestion to chemist Frederick Soddy.
Dr Margaret Todd
Periodic table
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The periodic table, also known as the periodic table of the elements, is an ordered arrangement of the chemical elements into rows and columns. An icon of chemistry, the periodic table is widely used
Liquid mercury. Its liquid state at standard conditions is the result of relativistic effects.
Graphite and diamond, two allotropes of carbon
Iron, a metal
Sulfur, a nonmetal