Quick clarification (1 Viewer)

[exa_boi87]

" Compare qualititavely the number of free electrons that can drift from atom to atom in conductors, semiconductors and insulators "

Syllabus dotpoint 3.T.4, is this referring to the ease of movement between the valence/conduction bands, through to higher energy states etc.. (eg: conductors - many electrons, bands overlap hence movement into higher bands relatively easy for electrons when under influence of electric field, semiconductors - energy required to move into conduction band, lower quantity of electron movement into conduction band, insulator - little-no flowing of electron into higher energy states)? As information regarding the physical amount of electrons that are free to 'drift' isnt in my textbook!

Thanks ..

 

[serge]

"for the physical amount of electrons"
it'll be different for each metal...
plus it says qualitatively not quantitatively
I'd just draw those 3 band pictures

 

[currysauce]

"for the physical amount of electrons"
it'll be different for each metal...
plus it says qualitatively not quantitatively
I'd just draw those 3 band pictures

quite right, quite right

u could just state # of electrons (obviosuly, not specifically)

metals > semi > insult

 

[exa_boi87]

great .. thanks guys

 

[sunjet]

This came up in CSSA 2005 if i can remember, i don't have my asnwer infront of me but i got 4/4.

I drew the valence/conduction bands for insulator, semi-conductor, conductor. Stated how tightly the electrons were held and how many free electrons there were, ie. in insulator there are few thus it is not a good conductor etc