A substance is dissolved in water, and the temperature of the surroundings decreases. Is this process exothermic or endothermic? Explain in 3 to 5 sentences
The process of dissolving a substance in water is generally an exothermic process, meaning it releases energy in the form of heat. When a substance dissolves in water, water molecules surround the solute particles, causing them to break apart and form new bonds with the water molecules. This process releases energy as the new solute-water bonds are formed. Therefore, as the temperature of the surroundings decreases during the process, it can be concluded that dissolving the substance in water is an exothermic process.
When a substance dissolves in water and the temperature of the surroundings decreases, it indicates an endothermic process. Endothermic processes absorb heat or energy from the surroundings to occur. In this case, the dissolution of the substance requires energy input which is taken from the surroundings, resulting in a decrease in temperature. The energy is needed to break the intermolecular attractions between the solute particles and to overcome the forces holding the water molecules together. As the energy is absorbed, the temperature of the surroundings decreases.
To determine whether this process is exothermic or endothermic, we need to understand the concept of enthalpy. Enthalpy is the total energy of a system. In an exothermic process, the enthalpy of the system decreases, and energy is released into the surroundings. In an endothermic process, the enthalpy of the system increases, and energy is absorbed from the surroundings.
When a substance dissolves in water and the temperature of the surroundings decreases, it indicates that energy is being absorbed from the surroundings. This implies that the process is endothermic because the enthalpy of the system is increasing. The solute particles break apart and mix with the water molecules, requiring energy input, which is why the temperature of the surroundings decreases.