Question

Un azotat al unui element E, cu numarul atomic Z si masa atomica A, se descompune termic, conform ecuatiei:
E(NO₃)₂ (s) ⇒ EO₂ (s) + 2NO₂ (g).
In urma reactiei se obtine oxidul care are masa cu 51.39% mai mica decat azotatul.
Identifica elementul E.

Answer 1

M,azotat= A,gE+ 2(14gN+48gO)= A+124  ,g/mol

M,oxid= A,gE + 32gO,    g/mol

M,oxid= M,azotat- 51,39/100M,azotat= 0,4861xM,zotat

A+32= 0,4861(A +124)----> a= 55g/mol-------> Fe

desi, nu cred ca Fe are oxidul FeO2...........................mai verifica ecuatia !!!