The electronic conductance depends on:
A. The nature and structure of the metal.
B. Composition of metallic conductor
C. The number of valence electrons per atom.
D. Temperature
E. Number of ions.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → A, B, C and D only
Electronic (metallic) conductance is due to the movement of electrons through the metal; it does not involve ions.
(A) The nature and structure of the metal. — True. The kind of metal and its crystal structure decide how freely the electrons can move (its band structure and packing), so conductance differs from metal to metal.
(B) Composition of metallic conductor — True. What the conductor is made of decides its conductivity: copper, silver, iron and alloys all have different values. The composition does not change while the current flows.
(C) The number of valence electrons per atom. — True. It decides how many electrons are free to carry the current.
(D) Temperature — True. Electronic conductance decreases as the temperature rises, because the vibrating metal ions scatter the electrons more.
(E) Number of ions. — False. Current carried by ions is electrolytic conductance, the conduction in electrolyte solutions and melts.
NCERT (2026-27 edition):
Conductance of Electrolytic Solutions – “… Electrical conductance through metals is called metallic or electronic conductance and is due to the movement of electrons. The electronic conductance depends on
(i) the nature and structure of the metal
(ii) the number of valence electrons per atom
(iii) temperature (it decreases with increase of temperature).”