after a chemical reaction ,the Total mass of reactants annd products
c)is not changed
After a chemical reaction ,the Total mass of reactants and products
Because the mass of the initial substances is equal to the mass of the reaction products.
Ответ:
3C2H4+2KMnO4+4H2O→3C2H4(OH)2+ 2MnO2+2KOH
HCl+H2O=H3O+ +Cl-
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