When an endothermic chemical reaction (the system) occurs inside a calorimeter containing water (the surroundings) and no heat e
scapes from the calorimeter, which of the following statements is true? a. Heat flows from the system to the surroundings and the temperature of the water increases.
b. Heat flows from the surroundings to the system and the temperature of the water decreases.
c. Heat flows from the system to the surroundings and the temperature of the water decreases.
d. Heat flows from the surroundings to the system and the temperature of the water increases.
b. Heat flows from the surroundings to the system and the temperature of the water decreases.
Explanation:
The laws of thermodynamics lets us know that energy is neither created nor destroyed but can be converted from one form to another. Also, energy transfer does accompany chemical reactions in the form of heat.
For an endothermic reaction, heat is absorbed by the system from the surroundings. This leads to a drop in the temperature of the surroundings as energy is removed.
This implies that the water temperature decreases.
The enthalpy of vaporization of H2O is higher than the enthalpy of fusion of H2O, therefore vaporizing the same mass of H2O would require more heat/energy than melting the same mass of H2O.
