Across
- 2. all the reactants, products, and any solvents
- 6. average bond breaking energy for the conversion of gaseous molecules into gaseous atoms; average of that bond in a range of similar compounds
- 7. the energy stored in chemical bonds that can be converted to heat
- 13. change which gives out energy to the surroundings
- 16. transfer of matter and energy is possible across its boundary
- 18. exchange of energy between a reaction mixture (system) and its surroundings when the reaction takes place at constant pressure; units = kJ mol-1
- 22. change which takes in energy from the surroundings
- 23. a measure of the average kinetic energy of the particles present
- 24. matter can neither enter nor exit, but can only move around inside
- 26. allows no transfer of matter, though energy may be transferred across the boundary
- 27. energy required to raise the temperature of one gram of a substance by one Kelvin
- 28. enthalpy change when 1 mol of a substance undergoes complete combustion in excess oxygen under standard conditions
Down
- 1. energy stored in chemical bonds of reactants and products
- 3. diagram showing the relative enthalpy of reactants and products, as well as the activation energy of a reaction
- 4. enthalpy change when molar quantities of reactants in their normal states react to form products in their normal states under standard conditions
- 5. the minimum energy needed in a collision between molecules if they are to react; the height of the energy barrier separating reactants and products during a chemical reaction
- 8. first law of thermodynamics
- 9. the study of heat changes that occur during chemical reactions
- 10. enthalpy change when 1 mol of a substance in its standard state is formed from its elements in their standard states
- 11. the apparatus that contains the reaction, thermometers or other measuring devices, the laboratory, and everything external to the reacting substances
- 12. apparatus for measuring the energy change during a chemical reaction (typically it is insulated from its surroundings and contains water)
- 14. state of a system at standard conditions
- 15. the enthalpy change for a reaction is the same whether it takes place in one step or a series of steps
- 17. the study of energy and how it is interconverted
- 19. 250C (298K) and pressure 100 kPa; denoted by superscript q or 0
- 20. can be neither created nor destroyed; it can only be converted between different forms’
- 21. a cycle of chemical equations showing the enthalpy changes for each equation
- 25. a form of energy