Energetics

A reaction that releases energy to its surroundings is…

• Exothermic
• Endothermic
• Neutral

Acid-base neutralisation reactions always cause an increase in temperature. This means these reactions are…

• Endothermic
• Exothermic

What happens to the temperature of the surroundings during an endothermic reaction?

• It increases
• It stays the same
• It decreases

What happens to the temperature of the surroundings during an exothermic reaction?

• It increases
• It stays the same
• It decreases

What is specific heat capacity?

• c in Q=mc∆T
• The energy needed to raise the temperature of one gram of a substance by one degree C
• For water it is 4.18 J/mol/ºC

Why is this reaction carried out in a styrofoam cup?

• To maximise heat energy loss to the surroundings
• To minimise energy loss to the surroundings
• To prevent gas loss

How can you calculate ∆H from bond energy values?

• ∆H=bonds made – bonds broken
• ∆H=bonds made x bonds broken
• ∆H=bonds broken – bonds made

If the reactants have more internal energy than the products, what kind of a reaction must have taken place?

• Exothermic
• Endothermic

If the reactants have less internal energy than the products, what kind of a reaction must have taken place?

• Exothermic
• Endothermic

Breaking bonds is…

• Exothermic
• Endothermic