Firstly, note that there IS A DIFFERENCE between a mixture and a compound. 

Mixture- no chemical reaction.

Compound- chemical reaction

A mixture, as named above, is when one substance or ingredient is distributed through another without any reaction taking place. This means that there has been no rearrangement of chemical bonds. Don’t worry if you have no idea what that means, we’ll discuss this much later. For now, simply remember that there has been no “reaction” between any substances in the mixture.

A compound, on the other hand, occurs when there is a reaction that causes the two or more ingredients that are combined to undergo a chemical reaction and change the shape and form of their chemical bonds. In simplest terms, something has caused the building blocks of each substance to change. There are a variety of reasons this may occur, including extreme heat or a magical trigger.

• Some basic discussion of the theory of phase transition. Don’t worry: this is not at all as difficult as it sounds. In fact, it is something you probably see on a daily basis when you leave your ice cream sitting too long or you create ice cubes for iced coffee in the summer. I will not go into detail on the mundane physics yet, but to boil it down, so to speak: solids, liquids, and gases are composed of particles known as atoms and molecules, which are groupings of two or more atoms. (Smallest particle is an atom, two or more atoms make a molecule).
  
• If these particles are packed closely together and moving slowly, that is what we observe as a solid. (The atoms of every phase are NOT packed equally tightly and experience different amounts of movement).
  
• If they are packed less closely and experience slightly more dynamic (changing or active) movement, we see it as a liquid.
  
• Gases have the least densely packed particles of the three, and those particles express very active movement.
  
• A phase transition is the process by which a solid becomes a liquid, a liquid becomes a gas, a gas becomes a solid, and so forth.

• Solid to Liquid: Melting
• Solid to Gas: Sublimation
• Liquid to Solid: Freezing
• Liquid to Gas: Evaporation or Boiling
• Gas to Solid: Deposition
• Gas to Liquid: Condensation

A solution is a mixture (remember the definition from above) in which a smaller quantity known as the solute is dissolved and spread throughout a larger quantity or the solvent. A solution can actually be a solid, liquid, or a gas. As an example, our own atmosphere, which contains many different elements, is actually a solution in gas form! (A solution is a small amount of something that is dissolved in a medium).

Remember that you are always encouraged to do outside research on a topic if you deem it necessary