Thermochemistry

Class 11 · Chemistry · 5 questions

Name: ____________________   Date: ____________

1. In an exothermic reaction, the enthalpy change is:

   • A Positive
   • B Negative
   • C Zero
   • D Infinite

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

   • A The speed
   • B The path taken
   • C Only the initial and final states
   • D The catalyst

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

   • A 0
   • B -1 kJ/mol
   • C 1 kJ/mol
   • D 100 kJ/mol

4. Bond breaking is:

   • A Exothermic
   • B Endothermic
   • C Neither
   • D Always a catalyst process

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

   • A Melts
   • B Boils
   • C Dissolves
   • D Burns completely in oxygen