energy changes (p1) Flashcards
What is the conservation of energy law?
Energy cannot be created or destroyed, it can only be transferred
What is an exothermic reaction?
A reaction that transfers (gives) energy to the surroundings
What is an endothermic reaction?
A reaction that takes in energy from the surroundings
What happens to the temperature of the surroundings in an exothermic reaction?
The temperature increases
What happens to the temperature of the surroundings in an endothermic reaction?
The temperature decreases
What happens to the energy of the reactants in exothermic reactions?
The reactants lose energy to form the products
What happens to the energy of the reactants in endothermic reactions?
The reactants gain energy to form the products
What are examples of exothermic reactions?
combustion, many oxidation reactions and neutralisation
What type of reaction are combustion reactions?
exothermic
What type of reaction are neutralisation reactions?
exothermic
What type of reaction are most oxidation reactions?
exothermic
What type of reaction takes place in hand warmers?
exothermic
What type of reaction takes place in self heating cans
exothermic
What type of reaction are thermal decomposition reactions?
endothermic
What is a thermal decomposition reaction?
The breakdown of a substance when it is heated