Question 9 of 10intermediate💡 UnderstandShort Answer3 marks

What happens when oxygen reacts with magnesium and sulfur. What are the main differences in the nature of products formed?

Correct Answer

When magnesium (a metal) reacts with oxygen, it burns with a dazzling white flame and forms magnesium oxide, which is a white powder.

When magnesium oxide is dissolved in water, it forms a basic solution that turns red litmus paper to blue.

When sulfur (a non-metal) burns in oxygen, it forms sulfur dioxide gas.

When sulfur dioxide dissolves in water, it forms sulfurous acid, which is acidic in nature and turns blue litmus paper to red.

The main difference is that metal oxides (like magnesium oxide) are basic in nature, while non-metal oxides (like sulfur dioxide forming sulfurous acid) are acidic in nature.

Exercise: Let Us Enhance Our Learning | Q: 6 | (Chapter: Page 15)
For More Understanding

Explanation

The chapter describes Activity 4.6 where magnesium ribbon burns to form magnesium oxide, which when dissolved in water gives a basic solution. Activity 4.7 shows that burning sulfur produces sulfur dioxide, which when dissolved in water forms sulfurous acid—an acidic solution. The key distinction is that metal oxides are generally basic while non-metal oxides are generally acidic.

Solution Steps

  1. Magnesium (a metal) reacts with oxygen to form magnesium oxide, a white powder

  2. Magnesium oxide dissolved in water forms a basic solution that turns red litmus paper blue

  3. Sulfur (a non-metal) reacts with oxygen to form sulfur dioxide gas

  4. Sulfur dioxide dissolved in water forms sulfurous acid, which is acidic and turns blue litmus paper red

  5. The key distinction: metal oxides are generally basic in nature, while non-metal oxides are generally acidic in nature