C P1 - Energy Changes Flashcards
What is an endothermic reaction?
An endothermic reaction is when energy is taken in from its surroundings
Name two examples of endothermic reactions.
Two examples of endothermic reactions are thermal decomposition and ice packs
What is an exothermic reaction?
An exothermic reaction is when energy is released into its surroundings
Name two examples of exothermic reactions?
Two exothermic reactions include combustion and neutralisation
What does a reaction profile show?
A reaction profile shows the overall energy change of a reaction
What is the overall energy change in an endothermic reaction?
In an endothermic reaction, the energy needed to break existing bonds is greater than the energy released making new bonds
What is the overall energy change in an exothermic reaction?
In an exothermic reaction, the energy released making new bonds is greater than the energy taken in breaking existing bonds
What is the difference called between the reactants and products in endothermic and exothermic reaction graphs?
The difference between reactants and products in endo and exothermic reactions is called the activation energy
What is the trend of endothermic reaction graphs?
In endothermic reactions, the products are at a higher energy level than the reactant. Ad the reactants form products, energy is transferred from the surroundings to the reaction mixture. The temperature of the surroundings decreases because energy is taken in during the reaction.
What is the trend of exothermic reaction graphs?
In exothermic reactions, the products are at lower energy than the reactants. When the reactants form products, energy is transferred to the surroundings. The temperature of the surroundings increases because energy is released during the reaction.
What is the activation energy?
Activation energy is the minimum amount f energy that colliding particles must have in order to react
What are the advantages of hydrogen fuel cells?
The advantages of hydrogen fuel cells are that no pollutants are produced and they can be a range of sizes
What are the disadvantages of hydrogen fuel cells?
The disadvantages of hydrogen fuel cells are that hydrogen is highly flammable and it is difficult to store
