RBSE Class 10 Science Activity 1.1 Solution -Chemical Reactions and Equations

RBSE Class 10 Science Chapter 1 “Chemical Reactions and Equations” activity 1.1 helps students understand how a chemical reaction takes place when magnesium ribbon is burned in air. In this activity, students observe the formation of a new substance called magnesium oxide. This experiment is important for understanding the basic concepts of chemical reaction.

In this post, we have provided the complete solution of Activity 1.1 including objective, materials required, procedure, observation, conclusion and MCQs and important questions.

Chemical Reactions and Equations Activity 1.1 

Objective

To observe the reaction of magnesium with oxygen and understand the formation of magnesium oxide

Materials Required

i. Magnesium ribbon

ii. Sand paper

iii. Spirit lamp/burner

iv. Tongs

v. Watch glass

 

Procedure

·     Clean a magnesium ribbon about 2 cm long by rubbing it with sand paper.

·     Hold it with a pair of tongs. Burn it using a spirit lamp or burner and collect the ash so formed in a watch glass as shown in figure, Burn the magnesium ribbon keeping it as far as possible from your eyes.

·     What do you observe?

Observation

Magnesium ribbon burns with a dazzling white light and changes into white powder. The white powder is magnesium oxide.

Explanation

This is a chemical reaction because a new substance Magnesium oxide is formed. The properties of Magnesium and magnesium oxide are different.

Conclusion

It is clear that Mg burns and changes into a new substance of new state, which is magnesium oxide (MgO).

MgO is formed by the reaction of magnesium with oxygen present in air.

Precautions

It would be betters if students wear eye protection. This experiment should be performed only in the presence of the teacher.

 

Chemical Equation

 2Mg + O₂ → 2MgO

 

Type of Reaction

The reaction involved in this activity is ‘Combination reaction’.

Viva Questions

Q1. What is the white powder formed after burning magnesium?

Answer

Magnesium oxide

Q2. Why is magnesium ribbon cleaned before burning?

Answer

To remove the oxide layer present on its surface.

Q3. Which gas from air reacts with magnesium?

Answer

 Oxygen

Key Learning Points

i.Magnesium burns in oxygen.

ii.Magnesium oxide is formed.

iii.A new substance is produced.

iv. This is a combination reaction.

Multiple Choice Questions

Q1. What is formed when magnesium ribbon burns in air?

(a)Magnesium chloride

(b)Magnesium sulphate

(c)Magnesium oxide

(d)Magnesium hydroxide

Correct answer - (c ) Magnesium oxide

Q2. Magnesium ribbon burns with which type of flame?

(a)Yellow flame

(b)Blue flame

(c)Green flame

(d)Dazzling white flame

Correct answer - (d) Dazzling white flame

Q3. Which gas present in air reacts with magnesium?

(a)Nitrogen

(b)Oxygen

(c)Carbon dioxide

(d)Hydrogen

Correct answer - (b) Oxygen

Q4. The reaction between magnesium and oxygen is a:

(a)Decomposition reaction

(b)Displacement reaction

(c)Combination reaction

(d)Double displacement reaction

Correct answer - (c ) Combination reaction

Q5. Why is magnesium ribbon cleaned before burning?

(a)To increase its weight

(b)To remove the oxide layer on its surface

(c)To cool it down

(d)To change its colour

Correct answer -(b) To remove the oxide layer on its surface