Acids and Bases
A lesson and worksheet about the three different kinds of chemical substances.
• Students will be able to name three types of chemical substances.
• Students will be able to identify chemicals as either acid, base or neutral.
• Students will understand how to test for the pH of a substance.
• Students will be able to explain why knowing the pH of a substance is important.
4th Grade - 5th Grade - 6th Grade
Print the reading comprehension worksheet passage and questions (see below).
Students should read the passage silently, then answer the questions. Teachers may also use the text as part of a classroom lesson plan.
There are three types of chemical substances: acids, bases, and neutral substances. They are classified according to which particles they release in solutions. Acids release hydronium ions, while bases release hydroxide ions. Hydronium and hydroxide ions combine to make water. Water is a neutral substance. When acids and bases are combined to make water, the leftover substances from the reactants create a salt. A common example of this reaction is the combination of hydrogen chloride with sodium hydroxide to create water and sodium chloride. Sodium chloride is common table salt.
Acids and bases have different properties that make them useful. Acids are used in batteries and in the production of plastics, metals and dyes. Your body also uses acids called amino acids to build proteins that create your muscles and other body tissues. Bases are often used in cooking. For example, baking soda is a base that makes the dough in cakes rise.