Test: Is Matter Around Us Pure (Easy) - Class 9 MCQ

The process of Electrolysis Fractional distillation is used in some cases.

A solution is a homogeneous mixture of two or more substances. The substance present in the largest amount is called the solvent, and the one present in the smaller amount is called a solute.

The options b) and c) represent true properties of colloidal solutions.

a) Colloidal solution shows a Tyndall effect. They scatter light and make the path of light visible through dispersion.

b) Colloidal solutions show Brownian Movement Which Is Ceaseless, random motion(of dispersed phase particles) in all directions over a large area.

c) Colloidal solution are heterogeneous. They are a two-phase system, dispersed phase and the dispersion medium. There is a definite surface of separation between each particle of the dispersed phase and the dispersion medium

d) Size of The Colloidal Particles between 1nm and 1000nm.

Dye is a mixture of ink in water.

Distillation is a process of separation of liquids based on the difference in their boiling points.

Since the boiling point of nitrogen and oxygen are very close to each other. Hence, fractional distillation is used to separate the components of liquid air.

Gold(Au)is found in its pure form in nature.

Magnetic separation is used to separate a mixture of two solid substances based on their magnetic properties. Since X and Y's mixture can be separated using magnetic separation, X must be a solid magnetic material, and Y must be a solid non-magnetic material. Since X is magnetic in nature, it must be iron.

When a saturated solution is heated, it becomes unsaturated, because it causes an increase in kinetic energy, leading to an increase in distance between the molecules of the liquid. So that the solute particles take free space present in the solvent. That is why saturated solutions become unsaturated on heating.

Simple distillation: This is good for separating a liquid from a solution. For example, water can be separated from salty water by simple distillation. This method works because the water evaporates from the solution, but is then cooled and condensed into a separate container. The salt does not evaporate, and the seat stays behind.

Bronze is an alloy of primary copper and tin. It is categorized as a mixture. Option B is correct.

Compound is a pure substance made up of two or more substances combined chemically indefinite (or constant) proportion by mass(or weight). When two or more elements combine chemically to form a new substance called a compound.

Centrifugation method is also used for separating cream from milk. When milk is rotated at high speed, the cream collects at the centre and removed through the outlet.

Impure Substances Are Made Up Different-different particles. Here milk is an impure substance as it contains proteins, lactose, calcium, water, fats, etc. The others are pure substances as they are made up of a similar type of particles.