Question

How is mass/volume percent concentration defined and for what types of solutions is it typically used?

Short answer

Mass/volume percent is mass of solute/volume of solution as a percentage and is used for solid-liquid mixtures.

Step-by-step solution

Understanding Mass/Volume Percent Concentration

Mass/volume percent concentration is defined as the mass of the solute (in grams) divided by the volume of the solution (in milliliters), multiplied by 100%. This type of concentration measure is denoted by the formula: \[\text{Mass/Volume Percent} = \left( \frac{\text{mass of solute (g)}}{\text{volume of solution (mL)}} \right) \times 100\%\]

Usage of Mass/Volume Percent

Mass/volume percent concentration is typically used for solutions where the solute is a solid and the solvent is a liquid. A common example is when determining the concentration of a solid dissolved in a liquid, like salt in water, which benefits from a measure that considers both mass and volume.

Key concepts

Solute

The solute is the component of a solution that is present in a lesser amount compared to the solvent. In solid-liquid solutions, it is usually a solid that dissolves in the liquid, which acts as the solvent.
For instance, when you dissolve table salt in water, salt is the solute and water is the solvent.
Solutes can vary widely in their properties:

• Nature: Solutes can be ionic compounds like salt, or molecular compounds like sugar.
• Solubility: This refers to how well the solute dissolves in the solvent. It can depend on factors like temperature and the nature of the solute and solvent.

Understanding the role and characteristics of the solute helps in comprehending how solutions are formed and how their concentrations can be measured.

Solid-Liquid Solutions

Solid-liquid solutions are mixtures in which a solid solute is dissolved in a liquid solvent. These solutions are ubiquitous in everyday life, from saltwater in the ocean to sugar dissolved in your coffee.
There are several characteristics of solid-liquid solutions:

• Homogeneity: Solid-liquid solutions are usually uniform, meaning the solute is evenly distributed throughout the solvent after thorough mixing.
• Saturation: A solution is saturated when no more solute can dissolve in the solvent at a given temperature.

Most solid-liquid solutions have limits on how much solute can be dissolved, which depends on the temperature and pressure. Understanding these limits is crucial for many scientific and industrial processes.

Concentration Measurement

Concentration measurement involves determining how much solute is present in a given amount of solvent or solution. The mass/volume percent concentration is a common way to express this for solid-liquid solutions.
It is particularly useful for quantifying how much of a solid substance is dissolved in a liquid.
Here's a brief overview of how it's calculated:

• Mass of Solute: The amount of dissolved solute is measured in grams.
• Volume of Solution: The total volume of the solution is measured in milliliters.
• Formula Application: Use the formula \[\text{Mass/Volume Percent} = \left( \frac{\text{mass of solute (g)}}{\text{volume of solution (mL)}} \right) \times 100\%\]

This type of concentration measurement is important in various fields, including medicine and environmental science, where knowing the exact concentration of a compound is crucial.