level: End of chapter
Questions and Answers List
level questions: End of chapter
| Question | Answer |
|---|---|
| Exothermic enthalpy changes, what values | negative △H values |
| Endothermic enthalpy changes have what values | Positive △H values |
| Enthalpy changes can be calculated experimentally using the relationship. And how is this written for a mole of defined substance? | Enthalpy change, q = mass of liquid x specific heat capacity x temperature change △H = -mc△T |
| What does the standard enthalpy change of formation relates? | Relates to the enthalpy change when 1 mole of a compound is formed from its element under standard conditions |
| Hess's law can be used to calculate what? | enthalpy changes for reactions that do not occur directly or cannot be found by experiment. |
| Is bond breaking ( endo/exo ) thermic | endothermic |
| Is bond making (endo / exo) thermic | exothermic |
| Average bond energies are often used because? | strength of a bond between 2 particular types of atom is slightly different in different compounds |