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DIRECIA GENERAL

NVMNT PREUNIVERSITAR

OLIMPIADA DE CHIMIE etapa judeean

21 februarie 2015

BAREM DE EVALUARE - Clasa a IX-a

Subiectul I..............................................................................................................................................20 puncte

A. ......................................................................................................................................8 puncte (2x4puncte)

a). Si4+

< Cl < Si < K+ < Cl

- < Ar < K

b). 5, 15, 24.

c). Ar > O > Cl > Si > Ca > Na > K

d) 142 g

B. ......................................................................................................................................12 puncte(3x4puncte)

a). 62,5 g sol H2SO4 49%

b). 30 g sol H2SO4 49%

c). 104,136 g sol H2SO4 49%

Subiectul II............................................................................................................................................25 puncte

a). Identificarea substanelor i scrierea ecuaiilor reaciilor chimice din schem....................15 p uncte

a- KClO3, b KCl, c-O2, d-HCl, e-Cl2, f-H2O, g-HOCl, h-NH3, i-NH4Cl, j-Cu(NO3)2, k-NH4NO3,

l-CuCl2, m-KOH, n-Cu(OH)2, o-[Cu(NH3)4](OH)2

b). Formarea legturilor ...................................................................................................... .........5 puncte

c) Aranjarea corect a moleculelor stabile i justificarea rspunsului ....................... .................5 puncte

O2 < HCl < Cl2 < NH3