Energetics and Equilibria Flashcards Preview

IGCSE Chemistry > Energetics and Equilibria > Flashcards

Flashcards in Energetics and Equilibria Deck (10)
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1
Q

What is an exothermic reaction?

A
  • a reaction which gives out energy to the surroundings, usually in the form of heat and shown by a rise in temperature
2
Q

What is an endothermic reaction?

A
  • a reaction which takes in energy from the surroundings usually in the form of heat and is shown by a fall in temperature
3
Q

What process is bond breaking?

A
  • endothermic

- energy must be supplied to break existing bonds

4
Q

What process is bond formation?

A
  • exothermic

- energy is released when new bonds are formed

5
Q

What is the value of an exothermic and endothermic reaction?

A
  • exothermic: negative because reaction is giving out energy
  • endothermic: positive because the reaction takes in energy
6
Q

What is the equation to calculate enthalpy change?

A
  • total energy absorbed to break bonds - total energy released in making bonds
7
Q

Describe dissolving, displacement, and neutralisation calorimetry reactions

A
  • take the temperature of the reagents ( make sure they’re the same), mix and measure the temperature at the end of the reaction or at intervals
8
Q

Describe combustion calorimetry reactions

A
  • put 50g of water in a copper can and record its temperature
  • weigh spirit burner and lid
  • heat the water until 50 degrees
  • measure temperate of water
  • weigh spirit burner and lid
9
Q

What is a reversible reaction?

A
  • a reaction where the products of the reaction can themselves react to produce the original reactants
10
Q

What is dynamic equilibrium?

A
  • a reversible reaction that take place under closed conditions can reach a dynamic equilibrium
  • both reactions are occurring
  • but the overall quantities of the substances remain the same