Răspunsuri

2014-06-10T20:35:06+03:00
Masa molara CaO=40+16=56g/mol
%O=16/56*100

masa molara H2O=2+16=18g/mol
%O=16/18*100

masa molara Na2O (cred ca asa vroiai sa scrii)=2*23+16=62g/mol
%O=16/62*100
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