<span>вычислите</span><span> </span><span>массовую долю</span><span> </span><span>кислорода</span><span> </span><span>в оксидах</span><span>: </span>
<span>а)</span><span> </span><span>хром</span><span> </span><span>(6)</span><span> </span><span>оксид</span><span> </span>
<span>б)</span><span> </span><span>хром</span><span> </span><span>(2)</span><span> </span><span>оксид</span>
<span>в)</span><span> </span><span>хром</span><span> </span><span>(3)</span><span> </span><span>оксид</span><span> </span>
<span>В ответе</span><span> </span><span>разместите</span><span> </span><span>оксиды</span><span> </span><span>по убыванию</span><span> </span><span>массовой доли</span><span>кислорода</span>
<span>_______________</span>
<span>w(эл)=Ar(эл)*n/Mr(вещ-ва) * 100%</span>
<span>а) CrO3 </span>
w(O)=16*3/(52+16*3)*100%
w(O)=48%
б)CrO
w(O)=16*1/(52+16*1)*100%
w(O)=23.5%
в) Cr2O3
w(O)=16*3/(52*2+16*3)*100%
w(O)=31.6%
Ответ:CrO3, Cr2O3, CrO