Dilution in Acids, Bases and Salts – Class 10 Science Experiment

Chapter Name: Acids, Bases and Salts

Activity Name: Dilution in Acids, Bases and Salts

Activity Description:

Required Items:

1. Test tubes
2. Water
3. Concentrated sulfuric acid (H2SO4)
4. Sodium hydroxide pellets (NaOH)

Step by Step Procedure:

1. Take a test tube and add 10 ml of water to it.
2. To the test tube containing water, add a few drops of concentrated sulfuric acid (H2SO4).
3. Slowly swirl the test tube to ensure proper mixing of the acid and water.
4. Touch the bottom of the test tube gently with your fingers.
5. Observe and note down the sensations you feel.
6. Determine whether the process is exothermic or endothermic based on your observations.
7. Repeat the above steps using sodium hydroxide pellets instead of sulfuric acid and record your observations.

Experiment Observations:

• During the addition of concentrated sulfuric acid to water, you may feel the test tube becoming warm or hot.
• The process of dissolving sulfuric acid in water is an exothermic process as it releases heat.
• When adding sodium hydroxide pellets to water, you might also observe the test tube getting warm.

Precautions:

1. Be cautious while handling concentrated acids and bases, as they can cause burns and injuries.
2. Always add acids slowly to water with constant stirring to avoid excessive local heating and splashing.
3. Follow the warning signs on the containers of concentrated sulfuric acid and sodium hydroxide pellets.

Lesson Learnt from Experiment:

The experiment demonstrates that the process of dissolving an acid or a base in water is exothermic, meaning it releases heat. It also highlights the importance of proper precautions while diluting concentrated acids to avoid accidents and injuries.