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Question
Find the odd one out and give its explanation.
Options
Potassium
Magnesium
Calcium
Beryllium
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Solution
Potassium
Explanation:
Magnesium, calcium, and beryllium all belong to Group 2 of the periodic table, collectively known as the alkaline earth metals. Potassium, however, belongs to Group 1, known as the alkali metals, which makes it much more reactive and gives it a different valency compared to the other three.
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