1) 2Na + 2H2O => 2NaOH + H2
Na2SO4 + Ba(OH)2 => 2NaOH + BaSO4
CuCl2 + Ca(OH)2 => Cu(OH)2 + CaCl2
BaO + H2O => Ba(OH)2
2) Formula chimica nisip => SiO2
MSiO2 = ASi + 2AO = 28 + 2*16 = 60g/mol
mSi=28g mO2=32g
%Si = mSI/M*100= Calculeaza !
% O = mO/M*100= Calculeaza !