Mr(H2SO4) = 2+32+(16*2) = 98
n(H2SO4)= 294/98=3 моль
n(Na2SO4)= n H2SO4
m(Na2sO4) =3 моль*142=426г
w(<span>Na2SO4</span>)=(400/426)*100\%=94\%
<span>2FeCl3 + 3Zn = 2Fe + 3ZnCl<span>2
</span></span><span>6Li + 2H3PO4 = 2Li3PO4 + 3H2
</span><span>2FeCl3 + 3Mg = 2Fe + 3MgCl<span>2
</span></span><span>3Fe + 4H2O = Fe3O4 + 4H<span>2
</span></span><span>2Al(OH)3 = Al2O3 + 3H2O</span>