Which statement best describes why industry uses heterogeneous catalysts?
a. they tend to be more stable.
b. they are all gases at room temperature.
c. they form strong bonds with reactant molecules.
d. they cause stronger bonds to form between molecules.

The correct answer is option D, They cause stronger bonds to form between molecules.

Explanation:

Heterogeneous catalysts are used for providing active reacting sites for the molecules. Usually the heterogeneous catalysts are used in a solid state with reactants in liquid and gaseous state. The reactant molecule get adsorbed on the surface of the catalyst and thus with the increased surface area,  the rate of reaction also increases. Also being in a different phase than the reactants helps the catalysts to be easily separated with little expenditure.

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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