Matter is any physical substance that possesses mass and occupies space (volume).  There are 3 types of matter, solids, liquids, and gases. 

An element consists of only one type of atom that cannot be broken down chemically. A compound is formed by the chemical combination of two or more different elements. 

Heterogeneous mixtures are non-uniform and there are clearly visible and distinct components that can easily be separated physically. For example, a salad. Homogeneous mixtures are uniform and  they have indistinguishable components. For example, salt water.  

Starting with acids, they taste sour and are often corrosive.  Acids are anything with a pH below 7 and they release hydrogen ions. They turn blue litmus paper red. Examples are vinegar and lemon juice. Bases on the other hand, taste bitter and feel soapy or slippery. Bases are anything with a pH above 7 and they release hydroxide ions. They turn red litmus paper blue. Examples are soap and drain cleaner.