Acids and bases are part of your daily life. You used some acids and bases at home. To clean your bathrooms you use a muriatic acids. The bread you eat contains baking soda which is a base. Know what are the characteristics of acids and the characteristics of bases as well. Neutralization is a chemical property of acids and bases when they are mixed, thy react with each other. You can say they neutralized each other. Learn a simple experiments on how to identify whether a sample is a base or an acid.
Acids and bases are part of your daily life. To clean your bathrooms you use muriatic acid. Sulfuric acid is the acid found in a lead storage battery used to start your car. The vinegar you used to improve the taste of your dishes is an acid. The bread you eat contains baking soda which is a base. Acids and bases were defined by chemist centuries ago in terms of the properties of their water solutions.
What is an acid?
When a nonchemist hears the word "acid", an image of some horrible corrosive liquid often comes to mind. Acids came from the latin words "acetum" which means vinegar. Acids are substances that release hydrogen ions when placed in water. Acids are substances whose water solutions has sour taste, turns blue litmus paper red. Acids are said to be proton donors and neutralize bases. The formula of acids are easy to recognize because chemists normally write the formula of an acid so that the first element to be symbolized is hydrogen (H), example is Hydrochloric acid (HCl). Acids are corrosive. The bad reputation that acids seem to have is it's tendency to react with certain. metals. One common example- battery acid will begin to dissolved unprotected iron parts of an automobile if it spilled and not flushed away with water.
What is a base?
Bases are substances that give hydroxide ion when placed in water. A base is a substance that is bitter to the taste. Bases feel soapy when they get them on your fingers. They are said to be proton acceptors. Bases neutralize acids. Bases turn red litmus blue. Bases often have an OH group of elements in their formulas. Common examples of bases are sodium hydroxide and potassium hydroxide. Bases are said to be caustic. They are able to burn and eat away your skin. It is wise to avoid direct contact with them as much as possible, particularly when they are in concentrated form, because they can produce serious injury.
It is a chemical property of acids and bases that when they are mixed, they react with each other and their acidic and basic properties disappear. You can say that they have neutralized each other. Neutralization is the reaction of an acid and a base to produce salt and water. Litmus is an indicator used to test whether a substance is acidic or basic. The disadvantage of litmus paper is that slightly acidic and slightly basic cannot be distinguished by the litmus paper tests.
The pH Scale
The pH scale is divided into 14 units. Neutral solutions have a pH of 7. Acids solutions have pH values of lesser than 7 while basic solutions have pH values of greater than 7. Changes in pH easily affect the growth of microorganisms, the agents of food spoilage. The pH of substance is closely monitored to prevent the growth of harmful bacteria.
To identify whether substances are acids or bases.
APPARATUS and MATERIALS:
Litmus paper (5 Red, 5 blue), 10 test tubes, test tube rack, dropper, big Erlenmeyer flask, sodium bicarbonate, milk of magnesia, different samples ( orange juice, baking powder solution, vinergar, powdered chalk solution, detergent solution, ampalaya, banana extract), water
Test water and different samples provided in the experiment as to their reaction with blue and red litmus paper. Fill-up the table under record of results.
RECORD OF RESULTS:
Sample name Reaction ACIDS, BASE or NEUTRAL
- Orange juice
- Baking powder solution
- Powdered chalk solution
- Detergent solution
- Milk of magnesia
- Banana extract
- Sodium bicarbonate
Prepared by: Jessie Agudo, B.S. Civil Engg'/Master of Art in Teaching Mathematics
QUESTIONS/APPLICATIONS: (Answers should be below each questions.)
1. Give three (3) characteristics of an acid.
2. Give three (3) characteristics of a base.
3. How do you recognize an acid based by their formula?
4. What do you mean when we say bases are caustic.
5. From the result of this experiment formulate the definition of an acid and a base.
College Chemistry Laboratory Manual
Dy, Eben et. al, "Chemistry", Science and Technology III '96