Quickly !
in its aqueous solution, 99.9% of a substance dissociates to release hydronium ions. which of the following is true for the substance?
it is a weak acid.
it is a weak base.
it is a strong acid.
it is a strong base.

It is a strong acid.

Explanation:

So, when 99.9% of a substance dissociates to release hydronium ions. It is considered as a strong acid.

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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