To what volume would I need to add water to the evaporated solution in problem 3 to get a solution with a concentration of 0.50 M?

Ions gain or lose electrons

No. an alpha particle is a pair of protons and a pair of neutrons, i.e. a helium

Where is the illustration?

The internal energy of the system we can term it as total potential energy and kinetic energy. energy flows out of the surrounding from the system then we can say that the internal energy of the final state is lower than its initials. the sign of  δesystem is negative.δesystem = efinal - einitial=-ve  efinal  ∠einitial.