Answer:
A) A warm wire
Explanation:
A warm wire has the most resistance. Heating the metal wire causes atoms to vibrate more, which in turn makes it more difficult for the electrons to flow, increasing resistance. Heating the wire increases resistivity.
Answer:
c. dioptre that's the answer.
<span>closing the switch completes the circuit</span>
Answer: ionic compound
Explanation:
An ionic compound is formed when one element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element and forms a positively charged ion called as cation. The element which accepts the electrons is known as electronegative element and forms a negatively charged ion called as anion.
For formation of sodium chloride:
Electronic configuration of sodium:
![[Na]=1s^22s^22p^63s^1](https://tex.z-dn.net/?f=%5BNa%5D%3D1s%5E22s%5E22p%5E63s%5E1)
Sodium atom will loose one electron to gain noble gas configuration and form sodium cation with +1 charge.
![[Na^+]=1s^22s^22p^63s^0](https://tex.z-dn.net/?f=%5BNa%5E%2B%5D%3D1s%5E22s%5E22p%5E63s%5E0)
Electronic configuration of chlorine:
![[Cl]=1s^22s^22p^63s^23p^5](https://tex.z-dn.net/?f=%5BCl%5D%3D1s%5E22s%5E22p%5E63s%5E23p%5E5)
Chlorine atom will gain one electron to gain noble gas configuration and form chloride ion with -1 charge.
![[Cl^-]=1s^22s^22p^63s^23p^6](https://tex.z-dn.net/?f=%5BCl%5E-%5D%3D1s%5E22s%5E22p%5E63s%5E23p%5E6)
The cations and anions being oppositely charged attract each other through strong coloumbic forces and form an ionic compound.