Dissolution: Effects of Ammonium and Calcium Chloride on Water Temperature

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Ammonium chloride caused the water to cool. This means that the Ammonium chloride drew energy from the water to help it dissolve. As a result of losing its energy, the water cooled down. Calcium chloride caused the water to warm up. This means that energy from the calcium chloride was released and the water absorbed this heat. As a result, the temperature of the water increased. 3. Since you are measuring the temperature of the water, let’s call that the system. Relative to the water, was this process of dissolution endothermic (absorbing energy) or exothermic (releasing energy)?

If the water is considered the system the the dissolution of the ammonium chloride was exothermic because the water lost energy. Since the temperature of …show more content…

Now lets call the ionic substance the system and the water the surroundings. Relative to the ionic substance, was this dissolution process endothermic or exothermic?

If the ionic substance is considered the system then in the dissolution of ammonium chloride, an endothermic reaction occurred. The system is gaining energy from its surroundings which are losing energy. The colder water around the ammonium chloride shows that it gave up energy to the substance. In the calcium chloride reaction, an exothermic reaction took place. This is because the system is releasing energy into its surroundings. The warmer water around the calcium chloride shows that it received energy from the substance. 5. Based on this, which compound is more stable as an ionic solid and which compound is more stable as an ionic solution? Which would you assume has a higher enthalpy in its pure solid form?

Calcium is more stable as an ionic solution. The reaction between this substance and water is exothermic. This means that it’s enthalpy is negative and that the bonds of the products are ultimately stronger. Therefore, ammonium chloride must be strong as a solid. The reaction between ammonium chloride and water was exothermic. The enthalpy of this reaction is positive, which means that the reactants of the products are more

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