Discrepant Events

Discrepant Events

Discrepant events are occurrences which defy our understanding of the world by presenting unexpected outcomes. These phenomena are often used in science demonstrations to grab the attention of an audience and engage visual learners, particularly young children.

1. Moving pepper

Aim: To study the effect of detergent on the pepper placed on the water surface.

Materials needed: Plate, Pepper powder, detergent (prill), water.

Procedure:

1. The plate was kept filled with water and in this pepper powder was spreaded evenly. 

2.Next to this prill detergent was kept in a small plate. I asked one of the student to dip his/her index finger in the detergent and place his/her finger exactly above the pepper in the plate. 

3.Then I asked the students to observe what happens to the pepper in the plate. 

4.They were amazed to see the pepper moving toward the periphery of the plate. I asked them to observe carefully.

Observation:

As the finger with detergent was placed just above the pepper in the centre of the plate, the pepper moved towards the periphery of the plate.

Question:

Why does the detergent move the pepper towards the side of the plate???

Explanation:

The detergent/soap molecules are different than water molecules. Detergent molecules don’t stick together and they also don’t stick to the water molecules. One part of the detergent molecule is attracted to water molecule while the other part wants to push water away. This makes the pepper to scatter. The detergent breaks the surface tension that water by disturbing the bonds between the water molecules. 

2. Underwater candle

Aim: To make the candle burn under water.

Materials needed: One glass bowl, candle, matchstick.

Procedure:

1.For this experiment, I kept one dry glass bowl on the table. In the bowl I placed a candle and allowed it to stand for atleast two three minutes. 

2.Then I poured water into the bowl letting half of the candle to be in water. 

3.Then I lit the candle, as it was burning the wax from the candle felt on the surface of the water. 

4.I asked the students to carefully observes what happens further. 
The

Observation:

As the burning candle reaches to the water surface it does not blow off but it also continues to burn under water. 

Question:

Why does the candle continue to burn under water?

Explanation:

The candle burns to continue under water as part of the wax surrounding the wick does not melt leaving a wall of protection around the wick. This wall allows the candle to burn even though the flame is already lower than the water surface. 

3. Gems art in water

Aim: To study the diffusion of food colour in the water.

Materials needed: Two gems packets, plate, warm water.

Procedure: 

1. For this experiment, I took a plain plate in which I placed the chocolate gems in the circular manner. 

2.It was taken in to consideration that the same colour marbles were not kept together in the plate. 

3.Also the gems were kept in such a way that every gems touches each other in the plate kept in circular manner.

4.Then I poured warm water slowly in the plate containing the chocolate gems. I asked students to observe carefully.

Observation:

After few seconds of adding the warm water through the gems on the plate, the colour with which the gems were coated started flowing out from it making a beautiful pattern on the water surface. 

Question:

How does these gems form colourful patterns in water???

Explanation:

Molecules in gas have lots of energy and spread out even more than molecules in a liquid. Warm water has more energy than cold water which means that molecules in warm water move faster than the molecules in cold water. Thus the food colour when added in the warm water moves along with the fast movement of molecules in the warm water. 

4. Lemon floating and sinking

Aim: To study the effect of salty water on the lemon.

Materials needed: Two glasses, water, salt and two lemons. 

Procedure:

1. In this experiment, both the glasses were filled third fourth of it with water. 

2.In one glass a teaspoon of salt was added, thus making it salty water and in the other glass it was a plain water. 

3.I asked them that what will happen if a lemon in both the glasses. Some told that they will float while some said that they will sink in the water. 

4.So to show what actually happens, I dropped lemon in both the glasses and asked students to observe what happens. 

           

Observation:

The lemon in salty water floats whereas the lemon in plain water sinks. The salty water makes the lemon to float.

Question:

Why does the lemon in plain water sinks while that in salty water floats???

Explanation:

Salty water is slightly denser than plain water. The lemon sinks in the plain water because the density of the lemon is greater than the density of water. The lemon floats in the salty water because the density of the lemon is lesser than the density of the salty water.