Unit 16

2. For a reaction to occur, the particles must collide, they must collide with the appropriate orientation, and they must collide with sufficient energy.
5. In a chemical reaction, the state in which the rate of the forward reaction equals the rate of the reverse reaction, so that the relative concentrations of the reactants and products do not change with time.
8. (of a chemical reaction or compound) occurring or formed with absorption of heat
9. The sum of all the areas of all the faces or surfaces that enclose a solid.
10. A measurement of how much solute exists within a certain volume of solvent
11. (thermodynamics) a thermodynamic quantity equal to the internal energy of a system plus the product of its volume and pressure
12. something that brings about a change in something else
13. Evolutionary timing methods based on the observation that at least some regions of genomes evolve at constant rates.

1. Result of diffusion where there is continuous movement of particles but no overall change in concentration
3. (of a chemical reaction or compound) occurring or formed with evolution of heat
4. rate at which reactants change into products over time
6. Energy needed to get a reaction started
7. A chemical reaction in which the products re-form the original reactants