Question

cati atomi se gasesc in: a)36g carbon ;b)460 g sodiu ;c)3.2g sulf

Answer 1

a) MC = 12g/mol      , n =m/M = 36/12 = 3 moli C

1 mol C....................N.A atomi = 6,022*10²³
3 moli C.........................x atomi

x = 6,022*3*10²³ = 1,8066*10²⁴ atomi C

b) MNa = 23g/mol    , n =m/M = 460/23 = 20 moli Na

1 mol Na........................6,022*10²³ atomi
20 moli Na.....................x =  1,2044*10²⁴ atomi

c) MS = 32g/mol,    n=m/M = 3,2/32 = 0,1 moli S

1 mol S.................6,022*10²³ atomi
0,1 moli S............x = 6,022*10²² atomi