This quick demonstration is a highly visual illustration of the use of acid-base indicators to determine pH. Milk of magnesia is mostly a suspension of magnesium hydroxide in water. Magnesium hydroxide is a strong base that readily neutralizes hydrochloric acid. Universal indicator is a mixture of several acid-base indicators. The changing colours of the indicator during this reaction help students to observe the pH changes that occur during neutralization.
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Teacher Demo/Student Activity: Charging by Contact
Categories: Lab/Student Activity, Teacher Demonstration
In this demo, a polyethylene strip is charged by rubbing with wool. The charged strip is then used to charge a neutral object, a pith ball, by contact. This demo can be done as a student activity. read more
Teacher Demo: What's in your breath? Neutralization Reactions
Categories: Teacher Demonstration
This activity involves the surprising neutralization reactions between the carbonic acid that forms when the carbon dioxide in one's breath reacts with water and calcium hydroxide. read more
Teacher Demo: Photosynthesis and Respiration: Complementary Processes
Categories: Teacher Demonstration
The cells of green plants contain the pigment chlorophyll in organelles called chloroplasts. Chloroplasts capture the Sun’s energy and store it―through photosynthesis―as chemical energy. The... read more