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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 - Science

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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

MCQ
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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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Chapter 3: Metals and Non-metals - Multiple Choice Questions [Page 22]

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NCERT Exemplar Science [English] Class 10
Chapter 3 Metals and Non-metals
Multiple Choice Questions | Q 25. | Page 22

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