Energy changes Flashcards
What are the two types of chemical reaction?
Endothermic and Exothermic
In a chemical reaction, energy can’t be (…) we say that energy is (…)
created or destroyed, conserved
What are four examples of exothermic reactions?
Combustion,
Neutralisation,
Oxidation,
Hand warmers
In exothermic reactions, ?
energy from the reacting chemicals is transferred to the surroundings.
What are the three examples of endothermic reactions?
Thermal decomposition,
Sports injury packs,
Citric acid + baking powder
What are the reactants for the endothermic reaction used in sports injury packs?
Ammonium nitrate + water
In endothermic reactions, ?
energy from the surroundings is transferred to the reacting chemicals
What are the two requirements for a reaction to happen?
Collisions
Activation energy
What is activation energy?
The minimum amount of energy that reacting particles must have for a reaction to occur
What are exothermic reaction graphs like?
high-low
What are endothermic reaction graphs like?
low-high
What information is contained within reaction profile diagrams?
Relative energies of reactants and products
Activation energy
Overall energy change
How can a catalyst increase reaction rates?
By lowering activation energy
Exothermic
Energy released by forming bonds (more or less) than energy required to break bonds
More
Endothermic
Energy released by forming bonds (more or less) than energy required to break bonds
less
