Solutions A and Bare both clear and colourles. When solution A is mixed with solution B, the temperature of the mixture increases and a yellow precipitate is observed. What can be concluded from these observations?

Solutions A and Bare both clear and colourles. When solution A is mixe

1.	Solutions A and Bare both clear and colourles. When solution A is mixed with solution B, the temperature of the mixture increases and a yellow precipitate is observed. What can be concluded from these observations?
Answer» The reaction is thermodynamically favoured ( spontaneous) at all temperatures The reaction is thermodynamically favoured ( spontaneous) only athigh temperature The reaction is thermodynamically favoured ( spontaneous) only atlow temperature The reaction is not thermodynamically favoured ( spontaneous) at any temperature. Solution :Since on mixing , temperature INCRESES, this MEANS that reaction is exothermic, i.e., energy factor FAVOURS the process.Since a precipitate is formed on mixing, this means entropy decreases,i.e.,entropy factor OPPOSES the process. `DeltaG= DELTAH-T DeltaS`. For reaction to be spontaneous, `DeltaG` should be `-ve`. As `DeltaH` is`-ve` and`DeltaS `is `-ve`, `DeltaG` can be -ve only if T is low.Hence, reaction will be spontaneous at low temeprature.