Final answer:
An endothermic reaction is a chemical reaction or physical change in which heat is absorbed from the surroundings, resulting in a decrease in the temperature of the surroundings.
Step-by-step explanation:
An endothermic reaction is a chemical reaction or physical change in which heat is absorbed by the system from the surroundings. Endothermic reactions require energy, and the energy is considered a reactant in the reaction.
One example of an endothermic reaction is the reaction between baking soda and vinegar.
When these two substances react, carbon dioxide gas is produced, and the surroundings become cooler.
Another example is the process of photosynthesis, where plants absorb energy from sunlight to convert carbon dioxide and water into glucose and oxygen.
In summary, some main characteristics of an endothermic reaction are the absorption of heat from the surroundings, a decrease in the temperature of the surroundings, and the requirement of energy as a reactant in the reaction.