1. Chem "Discovery Action" 1 Chemistry “ Discovery Action ” Topic 2 – The hazardous nature of acids and alkalis [Part1-Power Point version: 1.0]

2. Chem "Discovery Action" 2 Contents Cover P.1 Contents P.2 Members List P.3 Introduction P.4-5 The hazardous nature P.6-8 Safety precautions P.9 Treatment of the splash on the body P.10 Conclusion P.11-12 Reference P.13 End

3. Chem "Discovery Action" 3 Members List Leader: Chan Ngo Tin (4) Members: Cheung Ka Fai (7) Tsang Lok Hin (17) Wan Pak Lok (19)

4. Chem "Discovery Action" 4 Introduction This Power Point outlines the hazards involved with the use of acids, alkalies, and any harmful or corrosive materials. Also, we will point out that how do acids and alkalis harm our environment by neutralization.

5. Chem "Discovery Action" 5 Neutralization Acids and alkalis can be cancelled out when they are mixed together. This was demonstrated by filming the colour change of the acid-alkali mixture in which litmus solution was added. Sodium hydroxide solution was mixed with hydrochloric acid. The mixture was then evaporated under heat. When the solution has evaporated completely, some white solid remained which is sodium chloride

6. Chem "Discovery Action" 6 The hazardous nature of acids and alkalis

7. Chem "Discovery Action" 7 In daily life There are many things are containing acids or alkalis. E.g.: toilet cleaner and bleach. Failure to use these products could result in severe skin and eye irritation or burns from direct contact with acids and alkalis. Alkalis such as sodium hydroxide, potassium hydroxide, and ammonium hydroxide penetrate tissues more rapidly than acids and may cause irreversible eye damage if eye contact occurs. Alkali and acid vapors are irritating and may be corrosive to the respiratory system.

8. Chem "Discovery Action" 8 In the laboratory Concentrated strong acids are among the most dangerous chemicals in the laboratory when used or stored improperly. All strong inorganic acids release heat when mixed with water and nitric acid may release sufficient heat to burn combustible materials.

9. Chem "Discovery Action" 9 Safety precautions when handling acid and alkalis on the body 1. Do NOT store strong acids and strong alkalies together. If an accident results in breakage of the containers and they come into contact, they will react violently. 2. Do NOT store oxidizing corrosive materials including nitric acid and bleach, together with flammable solvents. The cleaning solution formed by adding sulfuric acid to sodium dichromate is a very strong oxidant which can violently react with organic matter..

10. Chem "Discovery Action" 10 Protective Clothing. A lab coat, in addition to protective gloves, is the minimum required protection for handling acids and alkalies. Protective gloves. Gloves shall be worn whenever acid and alkali solutions are handled. Lightweight PVC gloves should be sufficient to prevent incidental contact with dilute solutions. Eye and Face Protection. Splash-proof chemical goggles, or safety glasses with side shields and face shields are required when dispensing or handling concentrated acids and alkalies. Spill Materials. Neutralizing, absorbent materials should be obtained to control spills. Required appliances

11. Chem "Discovery Action" 11 Treatment of the splash of acids and alkalis on the body Do not attempt to clean up any large spills, especially if the vapors from the spill result in noticeable eye or respiratory irritation.. Small spills may be cleaned up by the person who caused the spill. Do not attempt to clean up any spills without wearing gloves, eye, and face protection. Acids and alkalies may affect footwear during clean-up of a spill. If there is any possibility of acid or alkali of footwear while cleaning up the spill, obtain shoe coverings or rubber boots. Control the spill with an appropriate neutralizing agent. Fill the material into a suitable container.

12. Chem "Discovery Action" 12 Conclusion Strong Acids and alkalis are very corrosive. When we using them we should be careful. Accidents with corrosive materials in which the material may splash on the body are common in the laboratory. Concentrated strong acids can cause severe and painful burns. Breathing vapors also result in irritation of the lungs and corresponding tissue.

13. Chem "Discovery Action" 13 Reference http://www.wastechengineering.com/papers/neutraliz ation_chemicals.htm http://www.wastechengineering.com/papers/neutraliz ation_chemicals.htm http://www.ehsservices.com/Library/Article_Strong_A cids.PDF http://www.ehsservices.com/Library/Article_Strong_A cids.PDF http://www.psfc.mit.edu/esh/caust.html http://144.214.35.115/public/safety/ msds/msds.htm http://www.hkedcity.net/resources/

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