1. Tardigrade
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  3. Chemistry
  4. In a reaction, C r2O72 - is reduced to C r3 + . What will be the concentration of 0.1 M K2C r2O7 in equivalent per litre? Cr2O72 -+14H++6e- arrow 2Cr3 ++7H2O

Q. In a reaction, $C r_{2}O_{7}^{2 -}$ is reduced to $ \, C r^{3 +}$ . What will be the concentration of $0.1 \, M$ $K_{2}C r_{2}O_{7} \, $ in equivalent per litre?
$Cr_{2}O_{7}^{2 -}+14H^{+}+6e^{-} \rightarrow 2Cr^{3 +}+7H_{2}O$

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Solution:

$\text{N} = \text{M \times }$ Valence factor
$\because N= 0.1 \times 6\left(2 Cr_{}^{6 +} + 6 e^{-} \rightarrow 2 \left(Cr\right)^{3 +}\right)$
$K_{2}C r_{2}O_{7}= \, 0.6 \, N.$

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