NIOS Class 10 Science and Technology Activity 4.2 Chemical Reactions and Equations

In this activity, we will perform an experiment showing chemical changes during a combination reaction.

 

NIOS Class 10 Science and Technology Project File

This activity is based on the NIOS class 10 science and technology chapter 4, Chemical Reactions and Equations

Aim of the activity

To observe the chemical reaction between calcium oxide and water and identify the type of reaction.

Material Required

   1.  Calcium oxide (quick lime)

   2. Water

   3. Beaker

   4. Glass rod

Procedure

We take a beaker and put a small quantity of calcium oxide. Now we add water to it and stir with a glass rod.

We observe the changes.

Observation

When we touch the outer surface of the beaker with our hand, it feels warm. We also see a milky white solution in the beaker.

Explanation

The reaction is exothermic because heat is released during this activity.

In this reaction, two reactants combine to form one product, calcium hydroxide, so the reaction is a combination reaction. This reaction is used in whitewashing and other constructive works.

 CaO_(s) + H₂O_(l) →Ca(OH)_2(aq)

Conclusion

We can conclude that

   1.  A chemical change occurs.

   2. The temperature increases, so the reaction is exothermic.

   3. The reaction is a combination reaction.

Frequently Asked Questions

   1. Why does the beaker become hot when quick lime is added to water?

Answer- Because the reaction is exothermic and heat is released.

   2. What is the product formed when calcium oxide reacts with water?

Answer – Calcium hydroxide (Ca(OH)₂)

   3. What type of chemical reaction takes place in the activity?

Answer – Combination reaction

   4. What is a combination reaction?

Answer: When two substances combine to form one product.