Suggest what happens to the other elements from which bread and wood are made when these substances are burned

carbon is major element and it remain as soot or char. but other elements such as N or S are made will be oxidized to their oxides NOx and SOx

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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