Cl2 ⇒ HCl <span>⇒ NaCl </span><span>⇒ PbCl2 </span><span>⇒ Pb(OH)2
1)Сl₂+H₂=2HCl
2)HCl+NaOH=NaCl+H₂O
3)2NaCl+Pb(NO₃)₂=PbCl2+2NaNO3
4)PbCl₂+2KOH=Pb(OH)₂+2KCl
</span>
H2S ⇒ S ⇒ SO2 ⇒ H2SO3 <span>⇒ PbSO3
1)</span><span>H₂S=S+H₂
2)</span><span>S+O₂=SO₂
3)SO₂+H₂O=H₂SO₃
4)</span><span>H₂SO₃+Pb(OH)₂=PbSO₃+2H₂O
</span>
S <span>⇒ SO2 </span><span>⇒ SO3 </span><span>⇒ H2SO4 </span><span><span>⇒</span> K2SO4
1)S+O₂=SO₂
2)2SO₂+O₂=2SO₃
3)SO₃+H₂O=H₂SO₄
4)</span>H₂SO₄+2KOH=K₂SO₄+2H₂O
Mr (N2O3) = 76 а.е.м.
w (N) = 2*14/76 = 0,368 или 36,8%
w (O) = 3*16/76 = 0,632 или 63,2%
<span>Mr (K</span>₃<span>PO</span>₄<span>) = 3 </span>· 39 + 31 + 4 · 16 = 212 (г/моль).<span>
Mr (Ca(OH)NO</span>₃<span>) = 40 + 16 + 1 + 14 + 3 </span>· 16 = 119 (г/моль).