А)2Mg+o2=2MgO MgO+2NO2=Mg(NO3)2 Mg(NO3)2+2KOH=1KNO3=Mg(OH)2
<span><span>NaCl</span>+<span>H2O</span> → <span>NaOH</span>+<span>HCl
</span></span><span><span>Na2O</span>+<span>H2O</span> → <span>2<span>NaOH</span></span></span><span><span>2
<span>Na</span></span>+<span>2<span>H2O</span></span> → <span>2<span>NaOH</span></span>+<span>H<span>2</span></span></span>
m AgNO3=250 *0,12=30г
mNaCl=300 * 0,04=12г
nAgNO3=30/248=0.12моль
nNaCl=12 / 58,5=0.2моль взят в избытке
NaCl+ AgNO3= AgCl+ NaNO3
1моль 1моль 1моль
nAgNO3=nAgCl=0,12 моль
m=n * M mAgCl=0,12 *170=20,4г