full transcript
From the Ted Talk by Shannon Odell: The most dangerous elements on the periodic table
Unscramble the Blue Letters
Some eltmnees are dangerous because of how they respond, react, or even explode in the outside environment. Top reactive elements reside in the first column of the periodic table and are known as alkali metals. They're rarely found in their pure eenmaletl form, as alalkis reilady donate the single electron in their outer sehll to whatever's around to form more stable ionic compounds. This can lead to vnoelit results— pure cesium, for example, bursts into flames when exposed to air, and explodes when dropped in water. Francium is likely the most rtcveiae alkali based on its position in the periodic table, but we don't know for sure. With a half-life of 22 minutes at most, it's thought that less than an ounce esxtis on Earth at any one time.
Open Cloze
Some ________ are dangerous because of how they respond, react, or even explode in the outside environment. Top reactive elements reside in the first column of the periodic table and are known as alkali metals. They're rarely found in their pure _________ form, as _______ _______ donate the single electron in their outer _____ to whatever's around to form more stable ionic compounds. This can lead to _______ results— pure cesium, for example, bursts into flames when exposed to air, and explodes when dropped in water. Francium is likely the most ________ alkali based on its position in the periodic table, but we don't know for sure. With a half-life of 22 minutes at most, it's thought that less than an ounce ______ on Earth at any one time.
Solution
- alkalis
- elemental
- elements
- reactive
- shell
- violent
- readily
- exists
Original Text
Some elements are dangerous because of how they respond, react, or even explode in the outside environment. Top reactive elements reside in the first column of the periodic table and are known as alkali metals. They're rarely found in their pure elemental form, as alkalis readily donate the single electron in their outer shell to whatever's around to form more stable ionic compounds. This can lead to violent results— pure cesium, for example, bursts into flames when exposed to air, and explodes when dropped in water. Francium is likely the most reactive alkali based on its position in the periodic table, but we don't know for sure. With a half-life of 22 minutes at most, it's thought that less than an ounce exists on Earth at any one time.
Frequently Occurring Word Combinations
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Important Words
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- water