Reactions and temperature changes
Energy is conserved in chemical reactions, so the total amount of energyThe capacity of a system to do work or the quantity required for mechanical work to take place. Measured in joules (J). For example, a man transfers 100 J of energy when moving a wheelbarrow. in the universe at the end of a reaction is the same as it was before the reaction.
When a chemical reaction happens, energy is transferred to or from the surroundings.
When energy is transferred to the surroundings, this is called an exothermicReaction in which energy is given out to the surroundings. The surroundings then have more energy than they started with so the temperature increases. reaction, and the temperature of the surroundings increases.
When energy is taken in from the surroundings, this is called an endothermicReaction in which energy is taken in. reaction and the temperature of the surroundings decreases.
A study of the energy changes involved in chemical reactions, whether exothermic or endothermic