An element has an atomic number of 19. Predict its valency and explain your reasoning.
ChemistryClass 9CBSEAnswered 12 May 2026
Answer
For an element with atomic number 19 (Potassium), the electron configuration is 2, 8, 8, 1. It has 1 valence electron. To achieve a stable octet, it is much easier for this atom to lose 1 electron than to gain 7. Therefore, its valency is 1.
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