With reference to the process of 'diffusion', consider the following statements: 1. Diffusion requires external mechanical force to intermix particles. 2. The rate of diffusion increases with an increase in temperature. 3. Solids and liquids can diffuse into liquids. Which of the statements given above is/are correct?

Correct Option The correct option is (c). Explanation Diffusion is the physical process where particles of different substances intermix on their own due to their random motion. It is a fundamental property of matter arising from the intrinsic kinetic energy of particles. Statement-wise Analysis - Statement 1 is Incorrect. Diffusion is a spontaneous process. It occurs naturally due to the random movement of particles from a region of higher concentration to a region of lower concentration. It does not require external mechanical force (such as stirring) to initiate the intermixing, although mechanical force can accelerate the distribution. - Statement 2 is Correct. The rate of diffusion is directly dependent on temperature. An increase in temperature provides particles with higher kinetic energy, causing them to move more vigorously. This increased speed leads to a faster rate of intermixing. - Statement 3 is Correct. Matter in various states can diffuse into liquids. Solids (e.g., sugar or salt crystals) and liquids (e.g., ink or alcohol) can diffuse into other liquids (e.g., water). Gases also diffuse into liquids, a process vital for aquatic life (e.g., dissolved oxygen in water). Key Takeaway: Diffusion is a spontaneous, temperature-dependent process driven by the kinetic energy of particles, allowing solids, liquids, and gases to dissolve and intermix within fluid media.

With reference to the process of 'diffusion',… - NCERT Class 9 Science MCQ

NCERT Class 9 Science — Chapter 1: Matter in our surroundings

mcqmedium

With reference to the process of 'diffusion', consider the following statements:

Diffusion requires external mechanical force to intermix particles.
The rate of diffusion increases with an increase in temperature.
Solids and liquids can diffuse into liquids.

Which of the statements given above is/are correct?

NCERT textbook question

From NCERT Science - class 9 · Page 3

Options

A1 and 2 only
B2 only
C2 and 3 only
D1, 2 and 3

Did you get this right?

Solution

Correct Option

The correct option is (c).

Explanation

Diffusion is the physical process where particles of different substances intermix on their own due to their random motion. It is a fundamental property of matter arising from the intrinsic kinetic energy of particles.

Statement-wise Analysis

Statement 1 is Incorrect. Diffusion is a spontaneous process. It occurs naturally due to the random movement of particles from a region of higher concentration to a region of lower concentration. It does not require external mechanical force (such as stirring) to initiate the intermixing, although mechanical force can accelerate the distribution.
Statement 2 is Correct. The rate of diffusion is directly dependent on temperature. An increase in temperature provides particles with higher kinetic energy, causing them to move more vigorously. This increased speed leads to a faster rate of intermixing.
Statement 3 is Correct. Matter in various states can diffuse into liquids. Solids (e.g., sugar or salt crystals) and liquids (e.g., ink or alcohol) can diffuse into other liquids (e.g., water). Gases also diffuse into liquids, a process vital for aquatic life (e.g., dissolved oxygen in water).

Key Takeaway: Diffusion is a spontaneous, temperature-dependent process driven by the kinetic energy of particles, allowing solids, liquids, and gases to dissolve and intermix within fluid media.

Your note

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