States of Matter

Adding salt (sodium chloride, NaCl) to water elevates its boiling point through boiling point elevation, a colligative property of solutions. The salt ions (Na+ and Cl-) disrupt the formation of water vapor at the surface, requiring more energy (higher temperature) for the water to boil. The boiling point increases proportionally to the concentration of dissolved particles. Sugar also raises boiling point but salt is the classic example. Oil doesn't dissolve in water, and chlorine is a gas.

Butter is not converted into a vapour state without passing through a liquid state.

Water is the purest substance in which hydrogen and oxygen combine with each other in a definite ratio, that is 1 : 8.

A mixture that does not have a uniform composition throughout its volume is called a heterogeneous mixture. For example: a mixture of salt and sulphur. 

Compound is a pure substance made up of two or more elements chemically combined in a fixed proportion by mass. Compounds cannot be separated into its constituents by simple physical method such as evaporation, filtration, distillation, solvent extraction or by using a magnet. Sugar (C₁₂H₂₂O₁₁) is a compound containing three elements carbon, hydrogen and oxygen in a fixed ratio by mass. Thus, it cannot be easily separated whereas ink, (dye in water), vinegar (acetic acid in water), seawater (water containing soluble salts) are mixtures and they can be easily separated by physical process. For example, dye can be separated from ink by evaporation, vinegar can be separated into its constituents by distillation. Moreover, salts can also be separated from seawater by evaporation.

Homogeneous mixtures have uniform composition throughout mass, i.e. the amount of solute and solvent is the same. Mixture of sugar and water has homogeneity at particle level.

A solution is a homogeneous mixture of one or more solutes dissolved in a particular solvent.

A solution is a homogeneous mixture. It is not a chemical compound.

Pure water is not a mixture because it doesn’t contain impurities.

Milk of magnesia is a colloid in which the dispersed phase is a solid and the dispersion medium is a liquid. Smoke has a gas as the dispersion medium and a solid as the dispersed phase. Cloud is a colloid in which the dispersed phase is a liquid and the dispersion medium is a gas. Milk is a colloid in which both the dispersed phase and the dispersion medium are liquids.  Thus, option (2) is correct.

Dispersed phase and dispersion medium are the two components of a colloidal solution. The rest of the statements are incorrect as: (1) Combination of all the three phases, i.e. solids, liquids and gases, is not necessary to form a colloid. (2) The solute-like component or the dispersed particles in a colloid form the dispersed phase. (3) A colloid does not settle down when left undisturbed, i.e. a colloid is quite stable. 

A solution is defined as a homogeneous mixture of two or more chemically non–reacting substances whose composition can be varied within limits. If a mixture is to be called a solution, it must satisfy the following two conditions: (i) The components of a mixture should be non-reacting. (ii) Mixture should be homogeneous. In a mixture of salt and water, salt and water do not react with each other. Moreover, there is homogeneity at the particle level, i.e. it tastes the same throughout. Thus, it is a solution. Mixture of starch and water and mixture of oil in water and mixture of sand and water are heterogeneous mixtures as they have non–uniform composition. Thus, they are not solutions.

A solution is defined as a homogeneous mixture of two or more chemically non–reacting substances whose composition can be varied within limits. If a mixture is to be called a solution, it must satisfy the following two conditions: (i) The components of a mixture should be non–reacting. (ii) Mixture should be homogeneous.

Mixture of copper sulphate and water, mixture of potassium permanganate and water and vinegar (mixture of acetic acid and water) are homogeneous mixtures as they have uniform compositions and the components of these mixtures are not visible to the naked eye or even under a microscope. 

It is a homogeneous mixture. Homogeneous mixtures have uniform composition throughout the solution.