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Question
Elements X, Y and Z have atomic numbers 6, 9 and 12 respectively. Which one:
- Forms an anion
- Forms a cation
- Has four electrons in its valence shell?
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Solution
The electronic configuration of:
X (6) = 2, 4
Y (9) = 2, 7
Z (12) = 2, 8, 2
- Y forms an anion as it needs just one more electron to complete its octet.
- Z forms a cation. It will lose its 2 electrons to achieve a stable electronic configuration, thus forming a cation.
- An ionic bond is formed between Y and Z and its molecular formula is ZY2.
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