When an object moves, stops moving, changes speed, or changes direction, how do scientists describe that condition?
a. a balanced set of forces
b. stable factors
c. frictional force
d. unbalanced forces

Kc = 0.040 for the system below at 450oc. if a reaction is initiated with 0.40 mole of cl2 and 0.40 mole of pcl3 in a 2.0 liter container, what is the equilibrium concentration of cl2 in the same system? pcl5(g) ⇄ pcl3(g) + cl2(g)

Describe the forces both attractive and repulsive that occur as two atoms move closer together.

Who examines and coordinates the cleanup of polluted sites?