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Question
How many electrons flow through a metllic wire if a current of 0·5 A is passed for 2 hours? (Given : 1 F = 96,500 C mol−1)
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Solution
I = 0.5 A
t = 2 hours = 2 × 60 × 60 s = 7200 s
Thus, Q = It
= 0.5 A × 7200 s
= 3600 C
We know that 96500 C = 6.023 × 1023 number of electrons.
Then,
3600 C = `(6.023 xx 10^23 xx 3600)/96500` number of electrons
= 2.25 x 1022 number of electrons
Hence 2.25 x 1022 number of electrons will flow through the wire
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