Compounds can be classified into 3 basic groups: acids, bases, and salts. However, not all substances are these!

Acids

In the 16^th century, alchemists had recognized that a certain group of substances had a sour taste to it. Therefore, they named this group "acids". (Latin for "sour")
Now, people can identify acids as any compounds that:

• turns blue litmus paper red
• taste sour
• reacts with some metals to produce hydrogen
• conducts electricity when dissolved in water

Where can I find acids?

Common house hold acids are:

• vinegar
• club soda
• lemon

Bases

Before they are called bases, they were once known as alkalis. The early scientists made bases by dissolving things like wood ashes, or seaweed in water, then evaporating the liquid. Bases are used as cleaning agents, and to make other cleaning agents (for example: soap!)
Now, people can identify any bases as a compound that:

• turns red litmus paper blue
• has a bitter taste
• feels slippery
• conducts electricity when dissolved in water

Where can I find bases at home?

Products like these are bases:

• Windex
• Drano
• Jergens

Salts

Salts results when a base solution reacts with an acid solution. The salts usually taste salty. *note: do not try anything in the lab unless you are instructed to do so!* You will find the salts when you evaporate the liquid that the base and acid was mixed in.

Why are salts so important?

The most common salt of all is the table salt (or if you want to be scientific: sodium chloride, NaCl). Long ago, salts were used to pay soldiers. And since there wasn't any type of refrigerator back in the olden days, we have used salts to preserve our food!