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Reactions

How Do We Know How Old the Earth Is?

Reactions is a show that uncovers the chemistry all around us. We answer the burning questions you’ve always wanted to ask, blending the worlds of science and every-day life.

How Do We Know How Old the Earth Is?

Season 4 Episode 31 | 4m 27s | CC

Since there’s no “established in” plaque stuck in a cliff somewhere, geologists deduced the age of the Earth thanks to a handful of radioactive elements. With radiometric dating, scientists can put an age on really old rocks — and even good old Mother Earth. For the 30th anniversary of National Chemistry Week, this edition of Reactions describes how scientists date rocks.

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