Chemistry · Thermochemistry
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During the formation of aqueous solution of any electrolyte:
- A
Heat is evolved
- B
Heat is absorbed
- C
Heat may be evolved or absorbed
- D
Electrolyte does not dissolve in water
A solution is a homogeneous mixture of two or more substances and can either be in the gas phase, the liquid phase, or the solid phase. The enthalpy change of solution refers to the amount of heat that is released or absorbed during the dissolving process (at constant pressure). This enthalpy of solution can either be positive (endothermic) or negative (exothermic). The heat may be evolved or absorbed during the formation of aqueous solution of electrolytes and it completely depends upon their behaviour and properties of electrolytes being used.
Heat is evolved when an exothermic reaction occurs, such as when Na+ ions are formed in water. However, not all electrolytes behave this way.
Heat is absorbed in endothermic processes, like the dissolution of ammonium chloride, where the heat of solution is positive. Yet, this is not the case for all electrolytes.
The enthalpy change of solution can be positive or negative. Therefore, heat may be either evolved or absorbed depending on the specific properties of the electrolyte.
This statement is incorrect as electrolytes are characterized by their ability to dissolve in water and dissociate into ions.
Tagged under Chemistry · Thermochemistry · 2018