1: Types of Solutions

Correct answer: C. Gas in liquid

Explanation: Solutions are classified by the physical state of the solute followed by that of the solvent. Oxygen is a gas, and water is a liquid; therefore oxygen dissolved in water is a gas-in-liquid solution, making option C correct. It is not gas in gas because water is not gaseous, not liquid in gas because oxygen is the solute, and not solid in solid because neither component is treated as a solid here.

Correct answer: B. Solid in liquid

Explanation: The type of a solution is named from the state of the solute followed by the state of the solvent. Glucose is a solid substance and water is a liquid solvent, so glucose in water is a solid-in-liquid solution. Thus option B is correct. A solid-in-solid solution would be an alloy, while options C and D involve a gas or a solid solvent, neither of which describes this aqueous glucose solution.

Correct answer: A. Solid in solid

Explanation: Brass is a solid alloy, mainly consisting of copper and zinc, which are both solid components under ordinary conditions. In solution classification, one solid acts as the solvent and the other as the solute; therefore brass is a solid-in-solid solution and option A is correct. The remaining choices require a liquid or gaseous solvent or solute, none of which describes this metallic alloy.

Correct answer: A. Gas in solid

Explanation: Classification is based on the physical state of the solute followed by that of the solvent. Hydrogen is a gas, while palladium is a solid metal that acts as the solvent. Hence hydrogen dissolved in palladium is a gas-in-solid solution, so option A is correct. It is not gas in liquid because palladium is not liquid, and the other choices assign an incorrect state to either the solute or solvent.

Correct answer: A. Solid in liquid

Explanation: Salt is a solid solute and water is a liquid solvent. Solution types are named by the state of the solute followed by the state of the solvent, so salt water is a solid-in-liquid solution. It is also an aqueous homogeneous solution when the salt dissolves completely. The other choices contain incorrect physical-state combinations; therefore A is correct.

Correct answer: A. Ethanol and water

Explanation: A liquid-in-liquid solution has a liquid solute and a liquid solvent. Ethanol and water are both liquids and are miscible, so they can form a uniform liquid solution. Oxygen in water is gas in liquid, salt in water is solid in liquid, and hydrogen in palladium is gas in solid. Therefore option A is the only correct example.

Correct answer: B. Salt in water

Explanation: A binary solution contains exactly two components: one solute and one solvent. Salt water contains water and dissolved salt, so it is a binary solution. Pure water has only one substance and is not a solution; water with salt and sugar has three components; oxygen alone is a pure substance, not a solution. Therefore B is correct.

Correct answer: B. Ternary solution

Explanation: The governing idea is that a solution is classified by counting all chemically distinct components, not merely the solutes. Here, water is the solvent and salt and sugar are two solutes, giving three components in total. Therefore, the mixture is a ternary solution, so option B is correct. A binary solution has only two components, option C is not a solution, and option D describes physical states rather than component number.

Correct answer: A. It helps identify the complete type, such as solid in liquid

Explanation: The state of the solvent identifies the overall state of a solution, while the solute state completes the description. For example, solid salt dissolved in liquid water is classified as solid in liquid. Solute state does not make every solution heterogeneous, remove the solvent, or produce water.

Correct answer: A. Salt water and ethanol-water

Explanation: A solution’s physical-state classification is mainly based on the state of its solvent. In salt water, water is liquid, and in an ethanol–water mixture both components are liquids; hence both examples are liquid solutions. Thus option A is correct. Air is a gas solution, brass is a solid solution, hydrogen in palladium is gas in solid, and camphor in nitrogen has a gaseous solvent, eliminating the other choices.

Correct answer: A. Brass and hydrogen in palladium

Explanation: Brass is a homogeneous solid solution, generally formed by mixing copper and zinc in the solid state. Hydrogen dissolved or absorbed in palladium is classified as a gas-in-solid solution because palladium is the solid solvent. Therefore option A contains only examples related to solid solvents or solid solutions. Air is gaseous, while soda water, salt water, and oxygen in water have liquid solvents, so the remaining pairs fail.

Correct answer: A. Air and chloroform in nitrogen

Explanation: Air is a homogeneous gas-in-gas solution in which nitrogen is the major solvent and other gases are solutes. In the stated example of chloroform in nitrogen, nitrogen is the gaseous solvent, so it is also a gaseous solution. Hence option A is correct. Salt water and soda water are liquid solutions, brass is solid, and hydrogen in palladium is gas in solid, so the other options are mixed-state pairs.

Correct answer: C. In sugar water, sugar is the solvent

Explanation: In sugar water, sugar is the substance that dissolves, so it is the solute. Water provides the dissolving medium and is the solvent. Salt in water and carbon dioxide in soda water are classified similarly. Nitrogen is treated as the major solvent in air because it is present in the largest proportion.

Correct answer: B. Solid in gas

Explanation: The classification is written as solute in solvent. Here the solute is solid and the solvent is gas, so the correct description is solid in gas, or solid dissolved in a gaseous medium. Camphor vapour in nitrogen is a textbook-type illustration. Option A reverses the two states.

Correct answer: C. Gas in solid

Explanation: The solute is the substance dissolved and the solvent is the medium. A gaseous solute in a solid solvent is therefore called gas in solid. Hydrogen absorbed by palladium is the standard example used here. Option A describes the opposite arrangement, while B has a liquid solvent and D has a gaseous solvent.

Correct answer: A. Soda water

Explanation: Soda water is the suitable daily-life example because carbon dioxide, a gas, is dissolved under pressure in liquid water. The solute is therefore gas and the solvent is liquid, giving a gas-in-liquid solution; option A is correct. Brass and zinc in copper are solid solutions or alloys, while air is primarily a gas-in-gas solution. Thus the distractors do not satisfy the required combination.

Correct answer: B. Oxygen in water

Explanation: In oxygenated water, oxygen is the gaseous solute and water is the liquid solvent. The resulting solution is liquid because its continuous phase, the solvent, is liquid; therefore option B is correct. Air is gas in gas, brass is a solid solution, and camphor in nitrogen is a solid solute in a gaseous solvent. Those combinations do not match a liquid solution with a gaseous solute.

Correct answer: A. Salt water

Explanation: In salt water, salt begins as a solid solute, while water is the liquid solvent. After dissolution, the homogeneous mixture remains liquid because the solvent forms the continuous phase, so option A is correct. Air is gas in gas, brass is a solid alloy or solid solution, and hydrogen in palladium is gas in a solid metal. Consequently, none of those alternatives has the required solid-solute, liquid-solution arrangement.

Correct answer: B. First check the solvent state, then the solute state

Explanation: To classify a solution, first identify the solvent and its physical state because it generally determines the overall state. Then identify the solute state to describe the combination, such as solid in liquid or gas in liquid. Colour, smell, container shape, and an assumed temperature are not the governing classification criteria.

Correct answer: A. Every solution is a homogeneous mixture

Explanation: A solution is defined as a homogeneous mixture in which one or more solutes are uniformly distributed in a solvent at the molecular or ionic level. Therefore every solution is a homogeneous mixture, making option A correct. A heterogeneous mixture has non-uniform composition and is not automatically a solution. Components do mix in a solution, and a solution may contain several substances, so options B, C, and D are false.

Correct answer: A. Gas in liquid solution

Explanation: The standard classification states the solute first and the solvent second. Since the solute is a gas and the solvent is a liquid, the correct name is gas in liquid solution, so option A is correct. Carbon dioxide dissolved in water is a familiar example. Option B reverses the states, option C changes the solute to a liquid, and option D changes it to a solid; therefore those distractors are chemically inconsistent.

Correct answer: A. Gas in liquid solution

Explanation: Before opening, carbon dioxide gas is dissolved in the liquid beverage under pressure. The beverage acts as the liquid solvent, so the solution is gas in liquid. Opening lowers the pressure above the liquid, allowing dissolved carbon dioxide to escape as bubbles. The bubbles do not make the original solution a solid or gas solution.

Correct answer: A. Copper

Explanation: In a solution, the component present in larger amount is generally treated as the solvent. Brass is a solid alloy in which copper is the major component and zinc is present in smaller amount. Thus copper is regarded as the solvent and zinc as the solute. Neither component is a gas, and alloys do have a solvent component.

Correct answer: A. Solvent

Explanation: Air is a homogeneous gaseous solution, not a single pure gas. Nitrogen forms the largest proportion, so it is treated as the solvent or dispersion medium, while oxygen and the other gases are solutes. It is not a sediment or an insoluble substance because all major gases are uniformly mixed.

Correct answer: A. Solute

Explanation: Oxygen is the substance being dissolved in water, so it is the solute. Water is present as the liquid medium and acts as the solvent. The gaseous state of oxygen does not prevent it from being a solute; solutes may be solids, liquids, or gases. The small amount also supports the solute classification.