The chemical equation represents a chemical reaction KBr + AgNO ⇒ AgBr + KNO3
Which two chemicals are products in the chemical change
A. AgNO3
B. KBr
C. KNO3
D. AgBr

the subject is in science

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.

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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