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Question
An element A is soft and can be cut with a knife. This is very reactive to air and cannot be kept open in air. It reacts vigorously with water. Identify the element from the following
Options
Mg
Na
P
Ca
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Solution
Na
Explanation -
Sodium is a third-period alkali metal which is a soft metal and highly reactive. sodium is stored under kerosene and whenever it comes in contact with air or water it reacts vigorously.
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