1: Types of Solutions

Correct answer: C. Deciding the full category only from solute state

Explanation: The state of the solute alone cannot determine the complete type of solution. A solid solute may form a liquid solution in water, a solid solution in a metal, or another type in a suitable medium. The solvent state determines the broad category, so option C describes the error. Checking homogeneity and distinguishing roles are useful steps.

Correct answer: A. Ethanol in water

Explanation: In ethanol in water, both ethanol and water are liquids, so the state combination is liquid in liquid. Because water is specifically the solvent, the mixture is also called an aqueous solution. “Aqueous” identifies the solvent as water, whereas “liquid in liquid” identifies the physical states. Air, brass, and hydrogen in palladium do not have water as solvent.

Correct answer: A. It is a liquid solution because water is the liquid solvent

Explanation: Carbon dioxide is the gaseous solute in soda water, but water is the liquid solvent and forms the continuous phase. Therefore soda water is a gas-in-liquid, or liquid, solution; it is not classified as gaseous merely because its solute is a gas. The broad category follows the solvent state, while the solute state describes the specific combination.

Correct answer: A. It is a solid solution because palladium is the solid solvent

Explanation: In this example, hydrogen is the gaseous solute and palladium is the solid solvent or medium. The broad category is determined by palladium’s state, so the mixture is a solid solution, more specifically gas in solid. The gas does not need to become a liquid or another gas for dissolution, and the example is treated as a homogeneous solid solution in this classification.

Correct answer: A. Air is a gaseous solution and brass is a solid solution

Explanation: Air is a homogeneous mixture of gases, so its solvent and final medium are gaseous; it is a gaseous solution. Brass is a homogeneous alloy in which metallic components are present in a solid medium, so it is a solid solution. Neither mixture is aqueous, and both are treated as homogeneous rather than heterogeneous in this context.

Correct answer: D. Aqueous solution is always based on number of components

Explanation: The term aqueous is based on the identity of the solvent: water must be the solvent. It is not a classification based on how many components are present; an aqueous solution may be binary, ternary, or contain more components. Binary depends on component number, while liquid solution and liquid-in-gas descriptions depend on physical states.

Correct answer: A. Amalgam

Explanation: An amalgam is an alloy in which mercury is one component. Mercury is liquid at room temperature, but it can be incorporated into a solid metallic phase, giving a solid solution such as a suitable amalgam. Thus the solute state can be liquid while the solvent and final solution are solid. Soda water is liquid, air gaseous, and salt water has a solid solute.

Correct answer: A. No, the solvent may be liquid or solid

Explanation: A gaseous solute does not determine the broad state of the solution. Oxygen dissolved in water gives a gas-in-liquid solution, while hydrogen dissolved in palladium represents gas in a solid medium. If both solute and solvent are gases, as in air, the solution is gaseous. Thus the solvent state, not solute state alone, decides the broad category.

Correct answer: A. No, it depends on solvent state

Explanation: A solid solute can dissolve in solvents of different states. Salt in water is a liquid solution, camphor in a gaseous medium can be a gaseous solution, and a metal solute in another solid metal can form a solid solution. Therefore the final category is governed by the solvent state, not simply by the solid state of the solute.

Correct answer: A. State of solvent

Explanation: Knowing that the solute is liquid does not identify the solution category. A liquid solute in water is liquid in liquid, while a liquid solute in a gaseous solvent is liquid in gas; a suitable solid solvent would give liquid in solid. Therefore the solvent state is essential for deciding the broad type and the state combination.

Correct answer: A. A liquid solute in ethanol

Explanation: A liquid solution is defined broadly by having a liquid solvent, whereas an aqueous solution specifically requires water as the solvent. In option A, ethanol is the liquid solvent, so the mixture can be a liquid solution but is not aqueous. The other three examples explicitly use water as solvent and are therefore aqueous as well as liquid solutions.

Correct answer: A. Hydrogen in palladium

Explanation: A solid solution is classified by the solid state of its solvent. In hydrogen in palladium, palladium is the solid solvent and hydrogen is the gaseous solute, so it is gas in solid and still a solid solution. Brass, zinc in copper, and copper in gold have solid metallic components on both sides and therefore represent solid-in-solid solutions.

Correct answer: A. Binary and liquid in liquid

Explanation: The number of components gives the first classification: two components make the mixture binary. The states give the second classification: both solute and solvent are liquids, so it is liquid in liquid. These descriptions are compatible and can be used simultaneously. The other options incorrectly change either the component count or the stated physical states.

Correct answer: A. Only that the mixture is homogeneous

Explanation: Homogeneity tells us that the composition is uniform and suggests a solution, but it does not identify the solvent, solute, their states, or the number of components. Those details are needed to classify the solution as aqueous, binary, liquid, solid, gaseous, or a particular state combination. The other options provide enough contextual information for the intended classification.

Correct answer: A. Binary solution

Explanation: Binary solution means only that two components are present; it does not specify whether the solvent is solid, liquid, or gas. Therefore the physical-state category cannot be inferred from the number two alone. Salt in water, brass, and air provide particular examples whose components and states can be identified from their composition. The missing information in the binary description is the physical state, especially that of the solvent.

Correct answer: A. Camphor in nitrogen

Explanation: Camphor in nitrogen can be treated as a two-component system: camphor is the solute and nitrogen is the gaseous solvent. Therefore it may be described as binary and gaseous, with the specific state combination solid in gas. The other options explicitly contain three substances or use water as the solvent, so they do not satisfy both conditions.

Correct answer: A. A solution of water, salt, and sugar

Explanation: The mixture containing water, salt, and sugar has three components. Water acts as the solvent, and because water is liquid, the resulting homogeneous solution is classified as a liquid solution. The air option names a gaseous mixture with fewer listed components, brass contains copper and zinc as a binary solid alloy, and hydrogen in palladium is a two-component solid solution. Hence option A satisfies both conditions.

Correct answer: C. Soda water is a gaseous solution because gas is dissolved

Explanation: Soda water contains a gas, usually carbon dioxide, as the solute, but water is the liquid solvent. Therefore it is a gas-in-liquid or liquid solution, not a gaseous solution. Air has a gaseous medium, brass is a solid alloy solution, and salt in water is a liquid solution because water is the solvent. The mistake in C confuses solute state with solution state.

Correct answer: A. In camphor in nitrogen, camphor is solute and nitrogen is solvent

Explanation: In camphor in nitrogen, camphor is the substance present in smaller amount and is the solute; nitrogen is the gaseous continuous medium and is the solvent. Option B reverses the roles in soda water, C reverses them in salt water, and D incorrectly calls palladium the solute even though it is the solid solvent in that example.

Correct answer: A. Calling soda water gaseous because the solute is gas

Explanation: Option A confuses the state of the solute with the state of the final solution. In soda water, the gas is the solute but water is the liquid solvent, so the solution is liquid. Options B, C, and D apply the correct rule by using the solvent state to identify the broad state of air, brass, and salt water.

Correct answer: A. Every aqueous solution is a liquid solution, but every liquid solution is not aqueous

Explanation: An aqueous solution specifically has water as its solvent. Since water is liquid under ordinary conditions, an aqueous solution is also a liquid solution. However, a liquid solution may use another liquid solvent such as ethanol, so it need not be aqueous. The other statements either reverse this relationship or deny that water can be a liquid solvent.

Correct answer: A. Many alloys can be examples of solid solutions

Explanation: Many alloys have metallic components uniformly distributed in a solid phase, so they are treated as homogeneous solid solutions. Brass, for example, is commonly classified this way. The word “many” is important because not every alloy must be perfectly homogeneous. Solid solutions do not require water, are not gaseous by definition, and are not always heterogeneous.