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Q112 (CDS-I/2023) Science & Technology › Basic Science (Physics, Chemistry, Biology) › Basic chemical principles Answer Verified

Consider the following statements regarding burning of magnesium ribbon in air: 1. White powder of MgO is formed. 2. It is an example of combustion reaction. 3. Heat and light are produced. Which of the statements given above are correct?

Result
Your answer: —  Â·  Correct: D
Explanation

The burning of magnesium ribbon in air is a classic chemical reaction where magnesium reacts with oxygen to form magnesium oxide (MgO). This reaction results in the formation of a white powder, which is the solid magnesium oxide [3]. It is classified as a combustion reaction because it involves a substance burning in the presence of oxygen [2]. Furthermore, the process is highly exothermic, releasing a significant amount of energy in the form of intense heat and a dazzling white light [1]. Scientific observations confirm that the reaction (2Mg + O2 → 2MgO) produces both thermal and radiant energy, making it a standard example of combustion and oxidation. Therefore, all three statements regarding the formation of white powder, the nature of the reaction as combustion, and the production of heat and light are scientifically accurate.

Sources

  1. [1] Science , class X (NCERT 2025 ed.) > Chapter 1: Chemical Reactions and Equations > Figure 1.1 Burning of a magnesium ribbon in air and collection of magnesium oxide in a watch-glass > p. 2
  2. [3] Science-Class VII . NCERT(Revised ed 2025) > Chapter 4: The World of Metals and Non-metals > Activity 4.6: Let us investigate (demonstration activity) > p. 51
  3. [2] Science , class X (NCERT 2025 ed.) > Chapter 1: Chemical Reactions and Equations > CuO +H Cu+H O 2 2 → Heat (1.29) > p. 13
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