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Question
The atomic number of four elements A, B, C and D are 12, 13, 15 and 3 respectively. The element which cannot form a cation is :
Options
A
B
C
D
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Solution
C
Element C has 15 electrons; so, the electronic configuration is 2 , 8 , 5. This element will gain 3 electrons in order to complete its octet; so, it cannot form cations.
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