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Periodic Classification of Elements — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10SciencePeriodic Classification of Elements5 Marks
Question
Atomic number of a few elements are given below:
10, 20, 7, 14
  1. Identify the elements.
  2. Identify the Group number of these elements in the Periodic Table.
  3. Identify the Periods of these elements in the Periodic Table.
  4. What would be the electronic configuration for each of these elements?
  5. Determine the valency of these elements.
✓

Answer

Atomic Number
10
20
7
14
Element
Neon
Calcium
Nitrogen
Silicon
Group Number
(8 + 10) = 18
2
(5 + 10) = 15
(4 + 10) = 14
Period Number
2nd
4th
2nd
3rd
Electronic Configuration
2, 8
2, 8, 8, 2
2, 5
2, 8, 4
Valency
Zero
2
(8 - 5) = 3
4

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