Questions

Dust particles such as coal dust(smoke) are fine particle of a solid (carbon in the case of smoke) dispersed in air. They are colloidal systems and the particles are charged either positive or negative. In an applied electrical field, they are attracted towards the opposite electrodes. Movement of the particles towards the electrodes is known as 'electrophoresis'. Hence electrophoresis is applied to remove smoke within the chimeny itself without allowing it to escape into the air and cause nuisance.

No, since the structure contains a char pointer while writing the structure to the disk using fwrite() only the value stored in the pointer n would get written. When this structure is read back the address would be read back but it is quite unlikely that the desired string would be present at this address in memory

Oxytocin is a mamallian hormone and also acts as neuro transmitter in the brain.