Let’s learn about the periodic table

This iconic chart holds information about all the known elements

The periodic table is instantly recognizable. This well-known chart is found in chemistry textbooks and on classroom walls. It lays out all the known elements and has been around in various forms for more than 150 years. But the version of that chart that Russian scientist Dmitri Mendeleev constructed in 1869 isn’t the same chart we see today.

Back then, his chart contained only 63 elements. They were all that were known. Mendeleev left gaps in his table where predicted, but not yet known, elements should fit. And once scientists found all the naturally occurring ones, they started bombarding two elements together to create new elements. Today, the table has 118 known elements.

In this video, Science News physics reporter Emily Conover explains what it takes to establish the validity of a true, new element — and name it. For the latest entrants, it took years of experiments and then the decision of a panel of judges.

Want to know more? We’ve got some stories to get you started:

Chemistry’s ever-useful periodic table celebrates a big birthday: Now 150 years old, this ‘table’ can take many forms, from block charts to spiral trees — and for good reason (11/21/2019) Readability: 8.2

The newest elements finally have names: Nihonium? Tennessine? These aren’t body parts or medicines. They’re among the names just given to the four newest superheavy elements. (6/8/2016) Readability: 8.5

Astronomers finally find the cosmic source of gold and silver: Gravitational waves point to answers for some longstanding mysteries of the universe (10/16/2017) Readability 8.1

Explore more

Scientists Say: Periodic table

Scientists Say: Atomic number

Explainer: The particle zoo

Go on a periodic scavenger hunt while you’re stuck at home. How many elements can you find without leaving your house?

From Science News: 150 years on, the periodic table has more stories than it has elements and How the periodic table went from a sketch to an enduring masterpiece.

Sarah Zielinski is managing editor of Science News for Students. She has degrees in biology and journalism and likes to write about ecology, plants and animals. She has two cats, Oscar and Saffir.

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