Mg(OH)2 (t)= MgO + H2O
30/58 = x/40;
x = (30*40)/58 = 1200/58 = 20.69 грамм
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1. 3NaOH+H3PO4=Na3PO4+3H2O
3Na(+)+3OH(-)+3H(+)+PO4(3-)=3Na(+)+PO4(3-)+3H2O
OH(-)+H(+)=H2O
2. BaCl2+H2SO4=BaSO4+2HCl
Ba(2+)+2Cl(-)+2H(+)+SO4(2-)=BaSO4+2H(+)+2Cl(-)
Ba(2+)+2Cl(-)=BaSO4
Х - CO2.
2CO+O2=2CO2;
CO2 + Ba(OH)2 = BaCO3 + H2O