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Question
Right or wrong sentence.
The valency of the elements in group 2 is 1.
Options
Right
Wrong
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Solution
The given sentence is wrong.
Explanation:
The valency of elements in Group 2 (the Alkaline Earth Metals) is 2, not 1.
- Reasoning: Elements in Group 2 have two electrons in their outermost shell (valence shell). To achieve a stable noble gas electron configuration, they readily lose these two electrons to form ions with a charge of + 2 (e.g., Mg2 +, Ca2+).
- Contrast: Elements in Group 1 (the alkali metals) have one electron in their outermost shell, which gives them a valency of 1.
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