5)).......................))
Сірка неметал, алюміній метал
<span>
2HNO</span>₃<span> + CuO = Cu(NO</span>₃)₂ + H₂<span>O
</span>2H⁺ + 2NO₃⁻ + CuO = Cu²⁺ + 2NO₃⁻ + H₂O
2H⁺ + CuO = Cu²⁺ + H₂O
Mr(K2O) = 39*2 + 16 = 94
W(K) = Ar(K) * n / Mr(K2O) *100% = 39*2 / 94 *100% = 83%
W(O) = Ar(O) * n / Mr(K2O) *100% = 16 *1 / 94 *100% = 17%