Is Matter Around Us Pure- Assertion & Reason Type Questions - Free AR

Cream can be separated from curd by centrifugation because this process separates components of a mixture based on differences in their densities and sizes by rapidly spinning the mixture. The denser particles move outward and collect at the bottom, while the lighter particles stay at the top. The reason given is false because it describes the separation of immiscible liquids, which is done using a separating funnel, not centrifugation. Therefore, assertion is correct, but the reason is incorrect.

Burning a match stick is an irreversible (chemical) change because when we burn it, it produces smoke and turns into ash.

The path of light becomes visible due to the Tyndall effect, where colloidal particles scatter the light, illuminating the beam's path.

Correct Answer:
C: (A) is true, but (R) is false.

Explanation:
The assertion is true because suspensions are heterogeneous mixtures where the solute particles remain suspended in the medium. However, the reason is false because the particles of a suspension are large enough to be visible to the naked eye, contrary to what the reason states

Correct Answer:

A: Both (A) and (R) are true, and (R) is the correct explanation of (A).

Explanation:

An unsaturated solution contains less solute than it can hold at a given temperature, meaning it can still dissolve more solute. The reason explains why such solutions are termed unsaturated.

Correct Answer:
D: (A) is false, but (R) is true.

Explanation:

The assertion is false because a compound can be broken down into simpler substances (its constituent elements) by chemical reactions. The reason is true because it accurately describes the composition of a compound, being made of two or more different types of elements chemically combined in a fixed proportion.

The assertion that a table salt solution in water is homogeneous is true because:

• The salt dissolves and mixes uniformly throughout the water.
• This creates a uniform composition.

The reason provided is incorrect because it:

• Defines a heterogeneous mixture rather than a homogeneous one.
• A homogeneous solution has the same composition everywhere, not different compositions.

A: Both (A) and (R) are true, and (R) is the correct explanation of (A).

Explanation:

Lemonade is a solution where sugar, salt, and other components are evenly dissolved in water, making it homogeneous. The reason explains the uniform distribution of particles, which is why the solution tastes the same throughout.

A: Both (A) and (R) are true, and (R) is the correct explanation of (A).

Explanation:

Alloys are mixtures because they retain the properties of their components and have variable compositions, despite the fact that their components cannot be separated by physical methods. For example, brass retains the properties of zinc and copper and has a flexible composition.