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Consider the following half cell reaction Cr ₂ O ₇²⁻( aq )+6 e ⁻+14 H ⁺( aq ) 2 Cr ³⁺( aq )+7 H ₂ O ( l ) The reaction was conducted with the ratio of [ Cr ³⁺ ]^2 [ Cr ₂ O ₇²⁻ ] =10⁻⁶ . The pH value at which the EMF of the half cell will become zero is ________. (nearest integer value) [Given : standard half cell reduction potential . E _ Cr ₂ O ₇²⁻, H ⁺ / Cr ³⁺ ^ o =1.33 ~V , 2.303 RT ~F =0.059 ~V ]

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0

Step-by-step solution

aligned & Cr ₂ O _ 7 (aq) ⁻²+14 H _ ( aq ) ⁺+6 e ⁻ 2 Cr _ ( aq ) ⁺³+7 H ₂ O _ ( ) & E _ R = E _ R ^0- 0.059 6 [ Cr ⁺³ ]^2 [ Cr ₂ O ₇⁻² ] [ H ⁺ ]¹⁴ & 0=1.33- 0.059 6 10⁻⁶ [ H ⁺ ]¹⁴ & 1.33 6 0.059 = 10⁻⁶ [ H ]¹⁴ & 135.254=-6-14 [ H ⁺ ] & 141.254=14 pH & pH = 141.254 14 =10.08 aligned

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