Connie was making sodium chloride by adding an acid to an alkali. She followed the progress of the reaction with a pH sensor .What else could she have used to detect when the reaction was complete?

Here are the equations for those reactions:

copper oxide + sulfuric acid → copper sulfate + water

CuO + H2SO4 → CuSO4 + H2O

copper carbonate + sulfuric acid → copper sulfate + water + carbon dioxide

CuCO3 + H2SO4 → CuSO4 + H2O + CO2

Copper oxide and copper carbonate are insoluble, so usually you add an excess (more than enough to react with all the acid) then filter the mixture. The excess solid stays in the filter paper as a residue. The copper sulfate solution drips through as a filtrate. This can be warmed to evaporate the water, leaving copper sulfate crystals behind.

Explanation:

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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