Thermochemistry

In an exothermic reaction, the enthalpy change is:

• 1 Positive
• 2 Negative
• 3 Zero
• 4 Infinite

Hess's law states that the enthalpy change of a reaction depends on:

• 1 The speed
• 2 The path taken
• 3 Only the initial and final states
• 4 The catalyst

The standard enthalpy of formation of an element in its standard state is:

• 1 0
• 2 -1 kJ/mol
• 3 1 kJ/mol
• 4 100 kJ/mol

Bond breaking is:

• 1 Exothermic
• 2 Endothermic
• 3 Neither
• 4 Always a catalyst process

Heat of combustion is the heat released when one mole of a substance:

• 1 Melts
• 2 Boils
• 3 Dissolves
• 4 Burns completely in oxygen