Navneet Science Journal Std 10 All Practical Answers: A Comprehensive Study Guide

Introduction

The Navneet Science Journal Std 10 is an invaluable resource for students preparing for their Science exams. It provides a comprehensive collection of practical answers to all the experiments and assignments included in the syllabus. This article serves as a companion to the journal, offering a structured and detailed guide to each experiment, along with tips and tricks for achieving success.

Practical 1: Separation of Pigments from Green Leaves

Materials Required:

• Green leaves
• Mortar and pestle
• Test tubes
• Ethanol
• Petroleum ether

Procedure:

1. Grind the green leaves in a mortar and pestle with a small amount of sand to extract the pigments.
2. Add the leaf extract to a test tube containing ethanol.
3. Shake the test tube vigorously and allow the pigments to separate into layers.
4. Transfer the upper layer of ethanol to another test tube containing petroleum ether.
5. Shake the test tube and allow the pigments to distribute between the two solvents.
6. Observe the different colors present in the layers.

Results:

• The ethanol layer will contain the green pigment chlorophyll.
• The petroleum ether layer will contain the yellow pigments xanthophyll and carotene.

Conclusion:

This experiment demonstrates the different types of pigments present in green leaves and their solubility in different solvents.

Practical 2: Photosynthesis - Effect of Light Intensity on the Rate of Photosynthesis

Materials Required:

• Elodea plant
• Test tubes
• Water
• Sodium hydrogen carbonate
• Light source
• Stopwatch

Procedure:

1. Fill several test tubes with water and add a small amount of sodium hydrogen carbonate to create a solution.
2. Place a sprig of Elodea in each test tube.
3. Set up a light source and vary the distance from the test tubes to create different light intensities.
4. Count the number of oxygen bubbles released from the Elodea per minute at each light intensity.
5. Plot a graph showing the relationship between light intensity and the rate of photosynthesis.

Results:

• The rate of photosynthesis will increase as light intensity increases.
• This is because light is required for the chemical reactions that take place during photosynthesis.

Conclusion:

This experiment demonstrates the effect of light intensity on the rate of photosynthesis and provides evidence for the importance of light in this process.

Practical 3: Respiration - Effect of Temperature on the Rate of Respiration

Materials Required:

• Germinating seeds
• Test tubes
• Water
• Thermometer
• Stopwatch

Procedure:

1. Fill several test tubes with water and place a germinating seed in each.
2. Place the test tubes in a water bath and vary the temperature of the water.
3. Measure the rate of respiration of the seeds by counting the number of carbon dioxide bubbles released per minute at each temperature.
4. Plot a graph showing the relationship between temperature and the rate of respiration.

Results:

• The rate of respiration will increase as temperature increases.
• This is because higher temperatures speed up the chemical reactions that take place during respiration.

Conclusion:

This experiment demonstrates the effect of temperature on the rate of respiration and provides evidence for the importance of temperature in this process.

Tips and Tricks for Success

• Read the instructions carefully before starting each experiment to ensure a thorough understanding of the procedures.
• Measure accurately when using graduated cylinders, pipettes, or other measuring devices.
• Control variables whenever possible to isolate the factor being tested.
• Repeat experiments to verify results and increase reliability.
• Record observations and data clearly and accurately in a lab notebook.

Why It Matters

Practical work is an essential part of science education as it allows students to:

• Develop their understanding of scientific concepts through hands-on experience.
• Enhance their problem-solving skills by designing and conducting experiments.
• Improve their critical thinking and analytical abilities by interpreting data and drawing conclusions.
• Foster their curiosity and interest in science.

Benefits

Students who engage in practical work:

• Have a deeper understanding of scientific concepts.
• Perform better on tests and exams.
• Are more likely to pursue careers in STEM fields.
• Become critical thinkers and problem solvers.

Compare and Contrast

Practical Work vs. Theoretical Learning

Conclusion

The Navneet Science Journal Std 10 All Practical Answers is an invaluable resource for students preparing for their Science exams. By following the detailed instructions and tips provided in this article, students can successfully complete their experiments, gain a deeper understanding of scientific concepts, and achieve success in their studies.