2Rb + 2H2O = 2RbOH + H2
Ответ: 3)
<span>MgO+<span>H2O=Mg(OH)2</span></span>
<span><span><span>MgO+2<span>HNO3=Mg(NO3)2+H2O</span></span></span></span>
<span><span><span>Al2O3+6<span>HNO3=2Al(NO3)3+3H2O</span></span></span></span>
<span><span><em>Al2O3</em><span> + 3H2O = 2Al(OH)3 </span></span></span>
<span><span><span><span>Al2O3 + 2KOH + 3H2O = 2K[Al(OH)4]</span></span></span></span>
<span><span><span><span><span>Fe(OH)2+H2O=Fe(OH)3</span></span></span></span></span>
<span><span><span><span><span><em>Fe(OH)3 + 3KOH = K3[Fe(OH)6] </em></span></span></span></span></span>
<span><span><span><span><span><em><span> Fe(OH)2+2HNO3=<em>Fe(<em>NO3)2+2H2O</em></em></span></em></span></span></span></span></span>
<span><span><span><span><span><em><span><em><em><span>2KOH+<span>H2S =K2S+2H2O</span></span></em></em></span></em></span></span></span></span></span>
Вещество - это то из чего состоят тела. а тела - это любой предмет.
следовательно: вещество из списка - <span>кислород</span>
CaCO3 + 2HNO3 --> Ca(NO3)2 + H2O + CO2
M(CaCO3)=40+12+16*3=100
x г --- 2 л
100 --- 22,4 л
x=2*100/22.4=8.93 г - карбонатов
10-8,93=1,07 г - некарбонатных примесей
1,07/10=0,107; 10,7%
<span>а) SO2 и SO3,</span>
<span>4FeS2+11O2=2Fe2O3+8SO2</span>
<span>2SO2+O2=2SO3</span>