Question

Calculati numarul de electroni continuti in:
a)3 g Au
b)5 moli CO2

Va rog repede!

Answer 1

a) Prima data aflam numărul de moli
n= m/M (molii= masa/masa molara )
n Ag = 3/197=0.0153 moli Ag
1 atom Ag are 79 electroni (sistemul periodic)
nr de electroni = 0.0153×6.023×10^23×79=7.245× 10^23 electroni
b) 1 molecula CO2 are 6+8×2 electroni = 22 electroni
1 mol ...........22×6.023×10^23 electroni
5 moli .................x
x= 5×22×6.023×10^23=6.625×10^25 electroni
Succes !