Matter is simply anything that takes up space.  The universe is full of it in many forms. Stars, galaxies, Earth's ocean, even you and me are made of matter.  Of course, matter comes in four (4) different forms or states.  That means four different forms of matter can take up space.  Matter can either be in the form of a solid, liquid, gas or plasma.  The difference between these forms are just the distance apart the molecules are, the temperature and charge their subatomic particles may have in the substance.  
   
Example:  Water can take three of the four forms of matter.  It can be in a solid state (ice), a liquid state (water), or a gas state (water vapor/steam).  The state that water takes depends upon the temperature its molecules are exposed to.  

Text Box: molecules in a solid are close together

 

 

 

 

 

Text Box: molecules in a liquid are further apart together

Text Box: molecules in a gas are very far apart

 

 

 

 

 

 

  
If you take any piece of matter an keep slicing in up, it will get smaller and smaller until you come to a piece that you will not be able to cut by physical or chemical means.  This little left over is called an ATOM. The ATOM is the basic building block of all things.  
   
Example:  If you were to take apart a LEGO house piece by piece, eventually you will come to one LEGO piece.  That one LEGO left over is like an ATOM.  You must have those individual LEGO pieces to build the LEGO house.  This is the same for the atom to matter. You need atoms to build different things that take up space (matter).

 

 

What Does an Atom Look Like?

An atom is made up of only three things.  Protons, Neutrons and Electrons  (we call these three things, SUBATOMIC PARTICLES).  That's it..  The protons and neutrons hang out in the atom's nucleus (the middle of the atom).  The electrons hang out around the nucleus.  Protons have a positive charge (+), electrons have a negative change (-), and neutrons have no charge (they're neutral).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

What Makes One Atom Different From Another Atom?

You may be asking yourself,  what determines the kind of matter an atom is?  Well, the answer to that question is simple.  Different kinds of atoms put together make up different kinds of matter.  The thing that makes the hydrogen atom different from the carbon atom is... are you ready...  THE NUMBER OF PROTONS IN ITS NUCLEUS. That's all there is to it.  All carbon atoms have 6 protons in the nucleus.  All oxygen atoms have 8 protons in its nucleus, and all uranium atoms have 92 atoms in its nucleus.

  
   
   
   
   
   
   
   
   
   
Much of the time, certain types of matter (substances) come in contact with other types of matter (substances). For example:  water, which is a types of matter, may come in contact with sugar.  Or, the blades of your lawn mower (steel) may come in contact with your lawn (grass). When this happens a reaction occurs.  The reaction can either be chemical of physical.  Below are examples of chemical and physical reactions.

 

Physical Reactions:  When you mix two or substances together and after mixing them you still have those original substances, a physical reaction has occurred.

Example:  If you mix peanut butter and jelly, you still have peanut butter and jelly

 

Chemical Reactions:  When you mix two or more substances together and an entirely new substance is created, a chemical reaction has occurred.

Example:  If you mix hydrogen and oxygen together you get an entirely new substance...  WATER.