Which of the following best explains why you sanded the copper wire before burning it? to create less friction between the copper and the tongs to make sure that copper metal was exposed on the surface of the wire to make the copper wire flammable to weaken the copper wire so it would be more reactive

The copper wire was sanded before burning in order to make sure that copper metal was exposed on the surface of the wire.

Answer: B

Explanation

The copper wire when placed in atmosphere without coating leads to oxidation of copper metal with respect to the impurities present in the atmosphere.

As copper is electropositive in nature, so electronegative ions present in the universe will try to react with copper and the copper will react easily with other elements.

So generally copper wire is coated with color or polymer coating.

In this case, the copper wire without any coating is sanded, so that the eddy sheets or polishing materials on friction with copper wire will remove the impurities by the electrostatic law of conservation of charges and charge transfer.

As the impurities are removed when copper wire is sanded, the copper atoms will be exposed on the surface of the wire leading to burning of copper in the copper wire.