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When hydrochloric aicd is addded to coba...

When hydrochloric aicd is addded to cobalt and nitrate solution at room temperautre, the following reaction takes place and the reaction mixture becomes blue. On cooling the mixture it becomes pink. On the basis of this information mark the corect ansewer.
`underset("pink")[[Co(H_(2)O)_(6)]]^(3+)(aq)+4CI^(-)hArr`
`underset("blue")[CoCI_(4)]^(2-)(aq)+6H_(2)O(l)`

A

`DeltaH gt 0` for the reaction

B

`DeltaH lt 0` for the reaction

C

`DeltaH=0` for the reaction

D

The sign of `DeltaH` cannot be predicted on the basis of this information

Text Solution

Verified by Experts

The correct Answer is:
A
Decrease in temperature will favour backward (endothermic ) reaction. Therefore , the forward reaction is exothermic i.e. `DeltaH > 0` for the reaction .
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MODERN PUBLICATION-EQUILIBRIUM-Objective A.(MCQs)
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