Question

Match the key terms with the descriptions provided. (a) an unstable solution that contains more dissolved solute than the maximum dictated by the solubility (b) a homogeneous mixture of two or more substances uniformly dispersed at a molecular or ionic level (c) moles of solute per kilogram of solvent (d) the substance being dissolved; usually the component of a solution that is present in the lesser amount (e) an intermolecular force between an ion and a polar molecule (f) the relative amounts of solute and solvent in a solution (g) mass of solute divided by mass of solution and multiplied by \(10^{9}\) (h) a solution that contains less than the maximum amount of solute possible in a stable system (i) a barrier that allows the passage of solvent but not of solute particles (j) a process of determining the concentration of one substance in solution by reacting it with a solution of another substance of known concentration (k) mass of solute divided by mass of solution and multiplied by \(100 \%\)

Short answer

None of the given descriptions can be matched with the given terms as the correct terms are not provided in the options.

Step-by-step solution

First Match

Begin by looking at description (a), 'an unstable solution that contains more dissolved solute than the maximum dictated by the solubility'. This matches the definition of supersaturated solution, though it's not actually listed between the options: in this case, none of the provided terms match it.

Second Match

Next, for description (b), 'a homogeneous mixture of two or more substances uniformly dispersed at a molecular or ionic level', the correct term is 'solution', but this term is also not provided so once again, none of the options match this description.

Third Match

Description (c), 'moles of solute per kilogram of solvent', can be matched with 'molality', but this term also isn't provided, so none of the options match.

Fourth Match

Description (d), 'the substance being dissolved; usually the component of a solution that is present in the lesser amount', can be matched with the term 'solute', but this term is not provided among the options.

Fifth Match

Description (e), 'an intermolecular force between an ion and a polar molecule', can be matched with the term 'ion-dipole force', which is also not provided in the options.

Sixth Match

Description (f), 'the relative amounts of solute and solvent in a solution', is matched with 'concentration', but the term isn't provided.

Seventh Match

Description (g), 'mass of solute divided by mass of solution and multiplied by \(10^{9}\)', is matched with 'parts per billion (ppb)', but the term isn't provided.

Eight Match

Description (h), 'a solution that contains less than the maximum amount of solute possible in a stable system' is the definition of 'unsaturated solution', which is not given as an option.

Ninth Match

Description (i), 'a barrier that allows the passage of solvent but not of solute particles' aligns with 'semipermeable membrane', but the term isn't provided.

Tenth Match

Description (j), 'a process of determining the concentration of one substance in solution by reacting it with a solution of another substance of known concentration', matches the definition for 'titration', but the term isn't provided.

Eleventh Match

Finally, description (k), 'mass of solute divided by mass of solution and multiplied by \(100 \%\)', matches the definition of 'percent by mass', but the term isn't in the options.

Key concepts

Supersaturated Solution

A supersaturated solution is a fascinating and unstable state of matter in chemistry. Imagine a solution that holds more solute than what it usually can at a given temperature. It’s like trying to squeeze extra sugar into a glass of iced tea when it's already full. Normally, if you add more solute, it won't dissolve. However, through careful cooling or evaporation, a supersaturated solution can actually hold extra solute temporarily.

This unstable condition means it is ready to release the excess solute at any disturbance, such as a shock or the addition of a seed crystal. When this happens, the excess solute rapidly crystallizes and separates from the solution.

• Key to forming a supersaturated solution is often temperature control, starting with a heated solution where solubility is higher.
• It is a prime example of why understanding chemical balances and solubility is crucial.

Whether for science experiments or industrial processes, knowing about supersaturated solutions helps us explore possibilities beyond standard solubility limits.

Solution Concentration

Solution concentration refers to the amount of solute present in a solution compared to the volume or weight of the solvent. Understanding this concept is central to solution chemistry because it influences physical and chemical properties. Think of concentration as the strength of a solution.

In practice, concentration can be expressed in several ways, each useful in different contexts:

• Molality: Moles of solute per kilogram of solvent. Useful when dealing with temperature-related studies since it remains constant as temperature changes.
• Molarity: Moles of solute per liter of solution. Commonly used for reactions and in lab settings due to its convenience in measuring liquids.
• Percent by Mass: Mass of solute divided by mass of solution, then multiplied by 100%. Ideal when dealing with solid mixtures or granulated materials.
• Parts Per Million (ppm) or Parts Per Billion (ppb): Helpful in analyzing very dilute solutions, like pollutants in water.

Grasping these methods is essential for lab work, industrial applications, and even everyday tasks like cooking or water purification. Mastering concentration calculations can open doors to accurate scientific experimentation and practical problem-solving.

Intermolecular Forces

Intermolecular forces are the forces that hold molecules together in a substance. They rank just below the strong forces that hold the atoms themselves together within a molecule. These forces are vital for understanding many properties of substances including boiling point, melting point, and solubility.

Some key types include:

• Ion-Dipole Forces: These occur between an ion and a polar molecule. They are crucial in dissolving ionic compounds in polar solvents like water.
• Dipole-Dipole Forces: Occur between two polar molecules and influence their interactions significantly.
• Hydrogen Bonding: A special and particularly strong type of dipole-dipole force, often seen in water molecules.
• London Dispersion Forces: Present in all molecules, these are the weakest types, due to temporary dipoles forming in atoms and molecules.

Intermolecular forces explain why oil and water don’t mix or why salt dissolves easily in water. They play a pivotal role in predicting how substances will behave in different environments and conditions.

Titration

Titration is an analytical technique used to determine the concentration of a solute in a solution. It involves adding a solution of known concentration, called the titrant, to the solution under analysis, until the reaction reaches completion. This point is often indicated by a color change, known as the endpoint.

The titration process is essential in various industries and labs for precise measurement of concentration, whether for medications, food quality control, or environmental monitoring. Here are a few aspects that make it indispensable:

• Acid-Base Titrations: Often involve indicators that change color at a certain pH, showing the completion of the reaction between an acid and a base.
• Redox Titrations: Involves reactions where electrons are exchanged, common in determining the concentration of oxidizing or reducing agents.
• Careful Calculation and Setup: Accuracy in measuring the titrant and sample volumes is crucial for reliable results.

Understanding titration helps in executing accurate lab analyses and developing an appreciation for quantitative chemical research.