Pages

Monday, May 23, 2011

7.1.1

Outline the characteristics of chemical and physical systems in a state of equilibrium


Equilibrium- a reaction in which the rate of the forward reaction is equal to the rate of the backward reaction. 
The amount of material in each condition (or state) remains the same but the process of change from one state to the other continues. Solid material continues to dissolve, and material that is in solution continues to crystallize. Dissolution and crystallization are occurring at the same rate. There is a balance between those two opposite reactions, this is dynamic (changes) equilibrium 

Physical Systems (example)
Bromine is placed in a sealed container at room temperature. Due to bromine being highly volatile it turns into gas close to room temperature and therefore forms a gas above the liquid bromine. Some particles will therefore gain more kinetic energy and turn into gas whilst particles that collide with the liquid particles of the bromine will lose kinetic energy and in turn will change state into liquid.


  (Only watch from 0-30 seconds)






Chemical Systems: (example)

The dissociation of hydrogen iodide (HI) and its elements H2 and I2. A purple iodine gas is produced and the tone of the colour purple increases. Although the purple colour stops to increase after waiting for a set amount of time and therefore gives evidence that equilibrium has been reached.

No comments:

Post a Comment