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Chemistry, 21.01.2021 14:00 destineenikole17
Descrieţi algoritmul de rezolvare a unei probleme ce presupune utilizarea unei reacţii chimice.
1. Notarea datelor problemei
2. Scrierea ecuației reacției chimice
3. Reprezentarea ecuației stoechiometrice
4. Calcularea masei de substanță necunoscută pe baza ecuației stoechiometrice, folosind regula de trei simplă
5. Scrierea proporției formate
6. Calcularea necunoscutei
7. Determinarea masei
1 punct
a)Completaţi ecuaţiile chimice următoare cu formulele chimice şi coeficienţii adecvaţi:
...Ca +... CaO
...CuCl2 +... CuSO4 + ... HCl
...KClO3... +...O2
...AgNO3 +... H2SO4... +...
...H2 +... N2 ...NH3
1 punct
b) numiți şi clasificaţi substanţele din primele 2 ecuaţii de mai sus. 1 punct
exemplu:Na2SO4=sulfat de sodiu - sare
Calculaţi randamentul reacţiei () de descompunere a calcarului( CaCO3), ştiind că se supun descompunerii termice 4t de calcar de puritate 80% şi se obțin practic 1344 kg de var nestins(CaO) . 2 puncte
500g soluţie de sodă caustică(NaOH) de concentraţie 16%, absoarbe o cantitate stoechiometrică de CO2 conform reacţiei :
2Na(OH) + CO2Na2CO3 +H2O.
Să se determine:
VCO2 absorbit de soluţia de sodă caustică ştiind că Vm=22,4 L/mol.
numărul de moli de Na2CO3format în urma reacţiei.
masa şi concentraţia soluţiei de Na2CO3finale.
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Answers: 2
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Descrieţi algoritmul de rezolvare a unei probleme ce presupune utilizarea unei reacţii chimice.
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