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प्रश्न
The atomic numbers of four elements P, Q, R and S are 6, 10, 12 and 17 respectively. Which two elements can combine to form a covalent compound?
(a) P and R
(b) Q and S
(c) P and S
(d) R and S
उत्तर
(c) P and S
Element P needs 4 electrons to complete its octet. They can be shared with element S, which needs only 1 electron to complete its octet.
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