Question
Identify the element with an electronic configuration
2,8,1 from among the following options.Solution
Sodium has the electronic configuration 2,8,1, indicating that it belongs to Group 1 (alkali metals) in the periodic table. The single electron in its outermost shell makes it highly reactive. Key Points: 1. Sodium’s atomic number is 11. 2. It reacts vigorously with water to form sodium hydroxide. 3. It is used in street lighting (sodium vapor lamps). 4. Stored in oil to prevent reactions with air or moisture. 5. Plays a key role in the human body for nerve transmission. Bee Facts: • Magnesium (a): Configuration 2,8,2, used in alloys. • Chlorine (b): Configuration 2,8,7, a halogen. • Hydrogen (c): Configuration 1, simplest element. • Sodium (d): Alkali metal, essential for life processes.
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