Question

Egalați redox următoarele ecuații, precizând procesele și caracterul substanțelor:
1) I 2 + HNO 3 → HIO 3 + NO + H 2 O

2) V 2 O 5 + Al → V + Al 2 O 3

3) S + HNO 3 → H 2 SO 4 + NO

4) I 2 + Cl 2 + H 2 O → HIO 3 + HCl

Answer 1

Răspuns:

$\bf1)\:\sf\underline{I_2^0} +H^{+1}\underline{\underline{N^{+5}}}O_3^{-2}\rightarrow H^{+1}\underline{I^{+5}} O_3^{-2}+\underline{\underline{N^{+2}}}O^{-2}+H_2^{+1}O^{-2}$

$\sf I_2^0\xrightarrow{-10e^-}2I^{+5}|\cdot3\:\:\:oxidare$

$\sf N^{+5}\xrightarrow{+3e^-}N^{+2}|\cdot10\:\:\:reducere$

I₂ → caracter reducător

HNO₃ → caracter oxidant

3I₂ + 10HNO₃ → 6HIO₃ + 10NO + 2H₂O

‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍ ‍

$\bf2)\:\sf\underline{V_2^{+5}}O_5^{-2}+\underline{\underline{Al^0}}\rightarrow\underline{V^0}+\underline{\underline{Al_2^{+3}}}O_3^{-2}$

$\sf V^{+5}\xrightarrow{+5e^-}V^0|\cdot3\:\:\:reducere$

$\sf Al^{0}\xrightarrow{-3e^-}Al^{+3}|\cdot5\:\:\:oxidare$

V₂O₅ → caracter reducător

Al → caracter oxidant

3V₂O₅ + 10Al → 6V + 5Al₂O₃

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$\bf3)\:\sf\underline{S^0}+H^{+1}\underline{\underline{N^{+5}}}O_3^{-2}\rightarrow H_2^{+1}\underline{S^{+6}}O_4^{-2}+\underline{\underline{N^{+2}}}O^{-2}$

$\sf S^0\xrightarrow{-6e^-}S^{+6}|\cdot3\!\!\!/\:\:1\:\:\:oxidare$

$\sf N^{+5}\xrightarrow{+3e^-}N^{+2}|\cdot6\!\!\!/\:\:2\:\:\:reducere$

S → caracter reducător

HNO₃ → caracter oxidant

S + 2HNO₃ → H₂SO₄ + 2NO

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$\bf4)\:\sf\underline{I_2^0}+\underline{\underline{Cl_2^0}} +H_2^{+1}O^{-2}\rightarrow H^{+1}\underline{I^{+5}}O_3^{-2}+H^{+1}\underline{\underline{Cl^{-1}}}$

$\sf I_2^0\xrightarrow{-10e^-}2I^{+5}|\cdot2\!\!\!/\:\:1\:\:\:oxidare$

$\sf Cl_2^0\xrightarrow{+2e^-}2Cl^{-1}|\cdot10\!\!\!/\:\:5\:\:\:reducere$

I₂ → caracter reducător

Cl₂ → caracter oxidant

I₂ + 5Cl₂ + 6H₂O → 2HIO₃ + 10HCl

Succes! <3