Răspuns:
P Z=15----> 1at are 15e
O Z=8---> 1at are 8e
total e: 2x15 +5x8=>70e/atom
M,P2O5=142g/mol
niu=m/M=28,4/142=0,2molP2O5
1mol are 6,023x10²³atomi
0,2mol.................N= 1,20X10²³ atomi
1atom....................70e
1,2x10²³at...........N=84,3X10²³ e
Explicație:
