Acid(s)-Base(s) Detective 

Gupta, Harendra Kumar Hyde Park Career Academy H.S

Objective(s): 1. Learn to identify and define acid and base. 2. Learn to define indicator and universal indicator. 3. Learn to prepare universal indicator at home. 4. Be able to classify household chemicals into acid(s) and base(s). Apparatus needed 1. Litmus papers (red and blue). 9. H2SO4 (0.1M).
2. Universal indicator (red 10. HNO3 (0.1M).
cabbage extract). 11. KOH(0.1M).
3. HCl (0.001, 0.01, 0.1 M). 12. Medicine droppers.
4. NaOH (0.001, 0.01, 0.1 M). 13. Milk of magnesia.
5. Test tubes. 14. Vitamin C.
6. Aspirin. 15. Club soda.
7. Tylenol. 16. Dish washer soap.
8. Advil.

Recommended Strategies: Students will be asked to name one acid and one base which they knew due to their known properties such as sour for acid and bitter for base. Then they will test the above with litmus papers. They will record the result as BLUE changes to RED for an acid and RED changes to BLUE for a base. Students will be asked to test six samples with litmus papers and asked to separate them out according to the colors. Then they will be asked to unwrap the samples and record formulas. They will be asked to define acid-base according to hydrogen and hydroxide ions. Students will be asked a question. If you are driving a car on the road,and suddenly the car stopped. What do you see on the dashboard? What is the needle pointing out? What is the needle called? If they say pointer then ask them, what is the other word for pointer? Then they will be asked to define indicator. Students will be given seven samples (wrapped). Then they will be told to separate them out using red and blue litmus papers. Now add six drops of liquid indicator then unwrap and place them according to concentrations written on the wrappings. Record the the results. Students will then be told that United Nations collected different ideas from different countries but those ideas were given to one country which in turn came up with one idea. Then students will be asked several questions and answer with universal idea. They will be asked to associate the above idea of universal to the above liquid indicator and let the students figure out the definition of Universal Indicator. Now the students will be told to use the above knowledge and apply the analysis to household chemicals.
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