Which statements are true?
The evaporation of water is an exothermic process.
When energy is transferred as heat from the system to the surroundings, is negative.
A combustion reaction is exothermic.
When energy is transferred as heat from the surroundings to the system, is negative.
for an exothermic reaction is positive.
for an endothermic reaction is positive.

The evaporation of water is actually an endothermic process, as it requires energy to convert liquid water into vapor, rather than releasing heat. This is one of those fascinating science facts that might surprise you! And while combustion reactions like burning wood or gasoline do indeed release energy, which makes them exothermic, the rest of the statements can really lead to some common misconceptions if we’re not careful.

In the grand world of thermodynamics, when we talk about exothermic reactions, we usually associate them with negative values, meaning energy is being released into the surroundings. Conversely, for endothermic reactions, energy is absorbed, resulting in positive . Keeping these definitions straight is key to mastering chemistry!