Classifying Acids and Bases
Purpose: To observe the typical properties of acids and bases.
Hypothesis: The typical properties of acids are identical to the typical properties of bases.
Materials:
* * Goggles * Well plate * 2 strips of magnesium ribbon * Sodium hydrogen carbonate (baking soda), NAHCO3 * Red litmus paper * Blue litmus paper * Conductivity tester
* Beakers of: * Tap water * Dilute bromothymol blue indicator * Dilute hydrochloric acid * Dilute sodium hydroxide * Eye droppers * Unknown acids and bases * Phenolphthalein
Procedure:
1. A data table was prepared to record observations. 2. Goggles were worn during the following experiments.
Part A: Acids
3. The teacher demonstrated the conductivity test using a conductivity tester and a beaker of tap water. 4. The teacher then added hydrochloric acid to the beaker. The observations were recorded. 5. The teacher then added hydrochloric acid to the beaker. The observations were recorded. 6. Five wells in a well plate were approximately half-filled with hydrochloric acid. The observations of the substance’s appearance were recorded. 7. The teacher distributed a strip of magnesium ribbon, a beaker of bromothymol blue indicator with an eyedropper, a strip of red litmus paper and a strip blue litmus paper. 8. One strip of magnesium ribbon was placed into one of the wells filled with hydrochloric acid. The observations of the substances’ appearance and reaction with each other were recorded. 9. The teacher added sodium hydrogen carbonate or also known as baking soda, into another well that was filled with hydrochloric acid. The observations of the substances’ appearance and reaction with each other were recorded. 10. Two drops of bromothymol blue indicator were added into a different well in the well plate that was filled with