Solutions

The wording names the solute first and the solvent second. Here the solute is solid and the solvent is gas, so the classification is solid in gas. Such combinations are uncommon in ordinary classroom examples, but the state-based rule still gives this answer. Gas in solid reverses the two states.

A solution type is written as solute in solvent. Since the solute in this question is a gas and the solvent is a solid, the correct description is gas in solid, written in Hindi as ‘ठोस में गैस’. Hydrogen dissolved in palladium is a familiar example. Option A reverses the solute and solvent states.

The type is named by stating the solute first and the solvent second. Here the solute is liquid and the solvent is solid, so the correct description is liquid in solid. A familiar class of examples is an amalgam, in which liquid mercury combines with a solid metal. The other choices reverse or change one of the stated physical states.

An amalgam is an alloy or solution involving mercury and another metal. Mercury is liquid at ordinary room temperature, while the other metal forms the solid component. In the state-based classroom classification, mercury as a liquid solute in a solid metal gives liquid in solid, or ‘ठोस में द्रव’. The other options describe different combinations.

Milk contains water, fats, proteins, and other substances dispersed as a colloidal system, not merely particles dissolved at the molecular level like salt in water. It may look uniform, but it is not a simple true solution. Therefore A is correct; the other choices are false because milk is a liquid and contains water.

Hydrogen is a gas, while palladium is a solid metal. When hydrogen is absorbed or dissolved in palladium, the gaseous solute is present in a solid solvent or solid medium. Therefore, it is classified as a gas-in-solid solution. The other choices reverse the states or introduce a liquid, so they do not fit this example.

Hydrogen is a gas, and palladium is a solid metal. Hydrogen can be absorbed or dissolved in palladium, so this is a gas-in-solid solution. Sugar in water is solid in liquid, carbon dioxide in water is gas in liquid, and ethanol in water is liquid in liquid. Therefore, only option A has the required states.

Camphor is treated as the solid solute and nitrogen as the gaseous solvent medium in this classification example. Therefore the combination is called a solid-in-gas solution. It is not gas in solid because nitrogen is the solvent, not the solid host; nor is it a liquid-based or solid-alloy example.

In the stated example, chloroform is the liquid solute and nitrogen is the gaseous solvent. The naming order is solute state followed by solvent state, so it is a liquid-in-gas solution. It is not gas in liquid because nitrogen is the solvent, and neither a solid solvent nor a liquid solvent is present in the described pair.

Salt water contains solid salt as the solute and liquid water as the solvent, so its correct classification is solid in liquid. It cannot be solid in gas because water is not a gaseous solvent. Air is gas in gas, brass is solid in solid, and carbon dioxide dissolved in water makes soda water gas in liquid, so those three pairs are correctly matched.

In the example of chloroform in nitrogen, nitrogen is the gaseous continuous medium and chloroform is the liquid component dispersed or dissolved in it, so it represents a liquid-in-gas solution. Glucose in water is solid-in-liquid, hydrogen in palladium is gas-in-solid, and zinc in copper is solid-in-solid. Thus only option A fits both stated conditions.

In salt water, salt is a solid solute and water is the liquid solvent. In oxygenated water, oxygen is a gaseous solute and water remains the liquid solvent. Thus the solute state changes from solid to gas while the solvent state stays liquid in both examples. The other pairs change the solvent state or do not provide two liquid-solvent examples.

The physical state assigned to a solution generally follows the state of its solvent, which is the continuous medium. A gas solvent gives a gaseous solution, a liquid solvent gives a liquid solution, and a solid solvent gives a solid solution. The solute state names the dispersed component but does not decide the overall state.

Particles in a true solution are extremely small and remain uniformly distributed, so they do not settle under ordinary conditions. Suspension particles are larger, can often be seen or scattered, and may settle on standing. Container shape, person, and colour do not define the distinction.

A solid-in-liquid arrangement does not fit the condition, so the example must contain a solid solvent and a liquid solute. Mercury is liquid, whereas sodium is a solid metal; a mercury–sodium amalgam can represent a liquid solute in a solid metallic solvent. Salt in water is solid in liquid, oxygen in water is gas in liquid, and air is gas in gas.

The governing concept is that the physical state of a solution is generally identified by the solvent, which forms the continuous medium. In this mixture, chloroform is the liquid solute but nitrogen is the gaseous solvent. Therefore the resulting solution is classified as gaseous. The solute need not be a gas, and neither solids nor water are involved, so B is correct.

The governing principle is that the solvent usually determines the final physical state of a solution. In hydrogen dissolved in palladium, hydrogen is the gaseous solute and palladium is the solid solvent, so the final solution is solid. Oxygen in water and glucose in water are liquid solutions, while chloroform in nitrogen is gaseous. Therefore option B is correct.

Uniformity tells us that the mixture may be a solution, while the number of components gives a separate classification. A solution containing three components is called ternary. Binary means two components, a single-component substance is not a mixture, and a suspension is classified by dispersed particles rather than simply by having three components.

The classification of a solution depends on the state of the final homogeneous mixture under the relevant conditions, not on a temporary state used during preparation. Brass is made by melting and mixing metals, but after cooling it becomes a solid alloy, so it is treated as a solid solution. Melting is only a processing step. B is false because molten metals can mix, and C and D contradict the composition and classification of brass.

A solution’s state description is written as solute state in solvent state. Air is gas in gas; hydrogen dissolved in solid palladium is gas in solid; and camphor dissolved in gaseous nitrogen is solid in gas. Glucose is a solid solute, but water is a liquid solvent, so glucose in water must be solid in liquid, not solid in solid. Therefore D is the incorrect classification.

To solve this, identify the state of the dissolved substance first and the medium second. Chloroform is a liquid solute, while nitrogen is a gaseous solvent; therefore chloroform in nitrogen is liquid in gas and matches both conditions. Ethanol in water is liquid in liquid, oxygen in water is gas in liquid, and hydrogen in palladium is gas in solid. Hence B is the only suitable example.

The required arrangement is a liquid solute distributed through a solid solvent or solid metallic matrix. An amalgam can represent this type: mercury is liquid, and it combines with another metal that forms the solid matrix in the resulting alloy. Air has a gaseous solvent, soda water has a liquid water solvent, and oxygen in water is gas in liquid. Therefore A is the suitable example.

A true solution is homogeneous, meaning its components are distributed uniformly throughout the sample. Clear appearance alone is not sufficient; a mixture may look clear while having different compositions in different regions. Cloudiness, solid-only composition, and absence of a solvent are not requirements of a solution.

The governing concept is that the first state names the solute and the second state names the solvent. Air is gas in gas, salt water is solid in liquid, and brass is solid in solid. In camphor in nitrogen, camphor is solid while nitrogen is gas, so the correct category is solid in gas, not gas in solid. Therefore D is the only incorrect match.

The naming rule writes the state of the solute first and the state of the solvent second. Therefore a gaseous solute in a liquid solvent is gas in liquid, and a solid solute in a liquid solvent is solid in liquid. A liquid solute in a solid solvent must be called liquid in solid, not solid in liquid. Option C reverses the states and is incorrect; A, B, and D follow the rule.