Question

7 g alchena decoloreaza total 200 ml solutie Br2 0,5 M.Alchena are formula moleculara?

Answer 1

V = 200 ml = 0,2 L

Cm = 0,5 M , Cm = niu/Vs

=> niu = CmxVs = 0,5x0,2 = 0,1 moli Br2

7 g          0,1 moli

CnH2n + Br2 => CnH2nBr2

miu           1

=> miu.alchena = 7x1/0,1 = 70 g/mol

=> 14n = 70 => n = 5

=> alchena = C5H10, propena