Energy In Chemical Reactions (continuted) Flashcards
(17 cards)
Q: What is an exothermic reaction?
A: A reaction that releases energy to the surroundings — usually as heat or light.
Example: Combustion, respiration, neutralisation.
Q: What is an endothermic reaction?
A: A reaction that absorbs energy from the surroundings.
Example: Photosynthesis, thermal decomposition.
Q: What is the effect of an exothermic reaction on temperature?
A: The temperature of the surroundings increases.
Q: What is the effect of an endothermic reaction on temperature?
A: The temperature of the surroundings decreases.
Q: Is dissolving ammonium chloride in water endothermic or exothermic?
A: Endothermic — the solution gets colder.
What does a reaction profile show?
The energy of reactants and products during a reaction
Q: What does an exothermic profile look like?
Products are lower in energy than reactants (downhill slope).
Q: What does an endothermic profile look like?
Products are higher in energy than reactants (uphill slope).
Q: What is activation energy?
The minimum energy needed to start a reaction (the height of the curve).
Q: Give two real-life uses of exothermic reactions.
Hand warmers, self-heating cans.
Q: Give a real-life use of endothermic reactions.
Instant cold packs for injuries
Q: Which reaction type is used in emergency heat packs?
Exothermic
Q: Which reaction type is used in cold packs?
Endothermic
Exothermic
Releases energy; temperature rises
Endothermic
Absorbs energy; temperature drops
Reaction Profile
Diagram showing energy levels during a chemical reaction.
Activation Energy
Energy required to start a reaction.
