What is the difference between a pure state and a mixed state?
2) so at t0, if i performed simultaneous measurment of a complete set of compatible variables on a system, how would a pure state differ from a mixed state?
3) for example a particle in a box, whould this be considred a pure state or a mixed one?
4) lastly how would |psi> evolve for both pure and mixed states after a measurement os performed ?

when it gains or loses electrons

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.

because if the tool that you are using is not balanced it there would be false mass.