Important Experiments in CBSE Class 10 Science

There are several important experiments that students should remember in CBSE Class 10 Science. These experiments help in understanding various concepts and principles of Science. Here are some of the important experiments along with their diagrams:

1. Experiment: To show that air is necessary for burning
- Material Required: Candle, matchstick, glass jar, and water
- Procedure:
- Light the candle using a matchstick.
- Place the candle inside the glass jar and close the lid tightly.
- Observe the candle for some time.
- Observation:
- The flame of the candle gradually extinguishes due to the lack of oxygen inside the jar.
- Inference:
- This experiment demonstrates that air (oxygen) is necessary for burning.

2. Experiment: To show that carbon dioxide is produced during respiration
- Material Required: Lime water, glass jar, straw, and candle
- Procedure:
- Fill the glass jar with lime water.
- Light the candle using a matchstick.
- Place the candle inside the jar and close the lid tightly.
- Allow the candle to burn for some time.
- Insert the straw into the jar without letting it touch the lime water.
- Blow air into the jar through the straw.
- Observation:
- The lime water turns milky due to the formation of calcium carbonate when carbon dioxide reacts with lime water.
- Inference:
- This experiment shows that carbon dioxide is produced during respiration.

3. Experiment: To determine the focal length of a convex lens using a lens formula
- Material Required: Convex lens, lens holder, screen, object pins, and meter scale
- Procedure:
- Fix the convex lens in a lens holder.
- Place the object pins at a certain distance from the lens.
- Adjust the position of the screen until a clear and enlarged image of the object pins is formed.
- Measure the distance between the lens and the screen.
- Measure the distance between the lens and the object pins.
- Calculation:
- Use the lens formula: 1/f = 1/v - 1/u, where f is the focal length, v is the distance between the lens and the screen, and u is the distance between the lens and the object pins.
- Inference:
- The focal length of the convex lens can be calculated using the lens formula.

These experiments are crucial for understanding various scientific concepts and principles. Understanding the procedures, observations, and inferences of these experiments will help students in their CBSE Class 10 Science examinations.