NIOS Class 10 Science and Technology Activity 7.2 Chemical Bonding

This activity helps us understand the nature of ionic compounds and their solubility in different solvents.

NIOS Class 10 Science and Technology Project File

This activity is based on the NIOS Class 10 Science and Technology(212) chapter 7, Chemical Bonding.

Aim of the activity

To observe the solubility of NaCl in water and in ethyl alcohol.

Materials Required

   1.    10 g of sodium chloride

   2. Two boiling tubes

   3. 10 mL water

   4. 10 mL ethyl alcohol

   5. String rod

Procedure

We take two boiling tubes and label them as '1' and '2'. Now we pour 10 mL of water into tube 1 and 10 mL of ethyl alcohol into tube 2.

 After that, we add 4 g sodium chloride to each tube and shake them vigorously, and observe the changes.

Observation

We notice that NaCl dissolves completely in water (tube 1) but remains undissolved in ethyl alcohol (tube 2).

Explanation

Sodium chloride is an ionic compound, and water is a polar solvent. So, water has partial positive and negative charges. Attraction force of these charges breaks the ionic bond in NaCl and surrounds the Na⁺ and Cl^- ions, allowing them to dissolve in the solution.

On the other hand, ethyl alcohol is an organic solvent and does not have enough polarity to break the strong ionic bonds of NaCl, so sodium chloride remains undissolved in it.

Conclusion

We can conclude through this activity that ionic compounds like sodium chloride dissolve in polar solvents like water but do not dissolve in less polar solvents like ethyl alcohol.

Frequently Asked Questions

   1. Why does NaCl not dissolve in ethyl alcohol?

Answer – Because ethyl alcohol is not polar enough to break the strong ionic bonds of NaCl.

   2. What type of bond is present in NaCl?

Answer – Ionic bond

   3. Can all ionic compounds dissolve in water?

Answer- Most of the ionic compounds dissolve in water, but some ionic compounds, like BaSO₄, AgCl, have low solubility.