3 H2S + 2 HNO3 = 3 S + 2 NO + 4 H2O,S:-2 → 0,升高2价N:+5 → +2,降低3价。所以 H2S配3,HNO3配2,以保证升降化合价相等(都是6)然后观察法配平其他的
3 H2S + 2 HNO3 = 3 S + 2 NO + 4 H2OS2- ---- S 2*3N5+ -----N2+ 3*2
3H2S+2HNO3 = 3S+2NO↑+4H2O
3H2S+2HNO3=3S+2NO+4H2O