Activity 1.1 Class 10 Science

  

Caution: This activity needs the teacher’s assistance. It would be better if students wear eye protection.

Material Required 

The following materials are used in this activity

1.  Magnesium ribbon

2. Spirit lamp or burner

3. Sandpaper

4. Watch glass

5. Tongs

6. Eye protector

Procedure 

•  Clean a magnesium ribbon about 2 cm long by rubbing it with sandpaper.

·      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 the 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 a white powder. The white powder is magnesium oxide.

Conclusion

Mg burns and changes into magnesium oxide (MgO), a new substance in a new state.

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

2Mg + O₂ → 2MgO

QuestionsAnswers based on the activity

1.  Why magnesium ribbon is cleaned before burning?

Ans.- When magnesium ribbon remains in the air, it gets covered with a layer of magnesium oxide, so this layer should be removed before burning.

2.  Give the chemical name of the white powder obtained?

  Ans.- Magnesium oxide 

3.  Write the chemical reaction when magnesium burns?

Ans- 2Mg + O₂ →2MgO

   

   4.. Why is it recommended to hold the magnesium ribbon with a pair of tongs?

Ans – Magnesium ribbon is burnt in the flame so to avoid any hazard to hand, we should hold the magnesium ribbon with a pair of tongs.

   5. Why is it recommended to protect your eyes during the experiment?

 Ans. During the activity, we burn the magnesium ribbon in spirit lamp or Bruner. There may be eye injury from the intense light so we must protect our eyes with eye protector.

   6. What do you observe during the burning of magnesium ribbon?

Ans – we can see a white dazzling light during the burning of magnesium ribbon and a white powder in the watch glass.

   7. What type of chemical reactions take place during the burning of the magnesium ribbon?

Ans - Magnesium ribbon reacts with oxygen during burning and form a white powder named magnesium oxide. It is a combination reaction.

   8. Write the chemical equation of the reaction during the magnesium ribbon.

Ans – 2Mg + O₂ →2MgO

   9. What is the chemical formula of the white powder collected in the watch glass during this activity?

Ans –  MgO

Related Topics

 1.  Activity 1.1 Video