Если исходные вещества показаны точно, то вариант только такой:2Na2So3+ TeO2+ 4HCl = Te + 4NaCl + 2H2SO4
<span><span>а) C + K2Cr2O7 + H2SO4 -> CO2 + Cr2(SO4)3 + K2SO4+ H2O
3 <span>C0</span></span> + <span>2 <span>K2Cr2VIO7</span></span> + <span>8 <span>H2SO4</span></span> → <span>3 <span>CIVO2</span></span> + <span>2 <span>Cr2III<span>(SO4)</span>3</span></span> + <span>2 <span>K2SO4</span></span> + <span>8 <span>H2O</span></span></span><span>C0</span> - <span>4e-</span> → <span>CIV</span><span>CrVI</span> + <span>3e-</span> → <span>CrIII</span>
в первом и третьем уравнениях оксиды металлов не диссоцируют на ионы.
3MgO+2H3PO4=Mg3(PO4)2+3H2O
3Li2O+2H3PO4=2Li3PO4+3H2O
Второе: CaCl2+2LiOH=2LiCl+Ca(OH)2
![Ca^{2+}+2Cl^{-}+2Li^{+}+2OH^{-}=Ca(OH)_2+2Li^++2Cl^- [/tex}</p> <p>[tex]Ca^{2+}+2OH^-=Ca(OH)_2](https://tex.z-dn.net/?f=Ca%5E%7B2%2B%7D%2B2Cl%5E%7B-%7D%2B2Li%5E%7B%2B%7D%2B2OH%5E%7B-%7D%3DCa%28OH%29_2%2B2Li%5E%2B%2B2Cl%5E-%20%5B%2Ftex%7D%3C%2Fp%3E%0A%3Cp%3E%5Btex%5DCa%5E%7B2%2B%7D%2B2OH%5E-%3DCa%28OH%29_2)
четвертое: Fe2(SO4)3+3Ba(OH)2=2Fe(OH)3+3BaSO4
![2Fe^{3+}+3SO_4^{2-}+3Ba^{2+}+3OH^-=2Fe(OH)_3+3BaSO_4](https://tex.z-dn.net/?f=2Fe%5E%7B3%2B%7D%2B3SO_4%5E%7B2-%7D%2B3Ba%5E%7B2%2B%7D%2B3OH%5E-%3D2Fe%28OH%29_3%2B3BaSO_4)