Question

Identify the following as characteristic of a solution, a colloid, or a suspension: a. Particles of this mixture remain inside a semipermeable membrane but pass through filters. b. The particles of solute in this solution are very large and visible.

Short answer

a. Colloidb. Suspension

Step-by-step solution

Understanding the characteristics of solutions

In a solution, the particles of solute are very small, typically molecules or ions. These particles are dissolved completely in the solvent, making the mixture homogeneous. Solutions can pass through both semipermeable membranes and filters without leaving residue.

Understanding the characteristics of colloids

In a colloid, the particles are larger than those in a solution but still small enough to remain dispersed and not settle out. These particles can pass through filters but are typically too large to pass through semipermeable membranes. This results in colloids being visibly heterogeneous under certain conditions (e.g., light scattering).

Understanding the characteristics of suspensions

In a suspension, the particles are large enough to be seen with the naked eye. These particles do not dissolve in the solvent and eventually settle down due to gravity. Suspensions cannot pass through filters or semipermeable membranes without the particles being retained.

Analyzing statement a

The description 'particles of this mixture remain inside a semipermeable membrane but pass through filters' matches the characteristics of a colloid. Colloids can pass through filters but not through semipermeable membranes.

Analyzing statement b

The description 'the particles of solute in this solution are very large and visible' matches the characteristics of a suspension. Suspensions have large, visible particles that do not dissolve and may settle out.

Key concepts

semipermeable membrane

A semipermeable membrane is a barrier that allows certain particles to pass through while blocking others based on size or type.
This membrane is crucial in allowing selective movement of substances.
For instance, when dealing with mixtures, only particles below a certain size can travel across a semipermeable membrane.
In the context of colloids, their particles are usually too large to pass through, hence they remain trapped.
However, in a solution, the particles are small enough to pass through both semipermeable membranes and filters.

Understanding how semipermeable membranes work helps clarify why certain mixtures behave differently in terms of particle distribution.
Overall, it's a fundamental concept in biology and chemistry, particularly in processes like osmosis and dialysis.

filtering particles

Filtering particles is one way to separate mixtures based on particle size.
In a solution, the particles are so small they pass through filters without obstruction.
In contrast, particles in a colloid, though larger, can still pass through filters.
This is because filters typically separate based on the size of the atoms or molecules.
Suspend materials, however, cannot pass through as easily due to their larger particle size.
Suspensions contain particles large enough to be seen with the naked eye, and they get trapped in the filter.

• Solutions: Completely filterable.
• Colloids: Filterable but cannot pass through semipermeable membranes.
• Suspensions: Not filterable as particles are too large.

Understanding these differences in filtering capabilities can help distinguish among solutions, colloids, and suspensions effectively.

particle size in mixtures

Particle size is a key factor in determining the behavior and classification of mixtures.
In a solution, the particles are incredibly small, typically ions or molecules, which makes the mixture homogeneous.
Colloids have larger particles that are still too small to settle out or be separated easily by ordinary filters.
These particles are large enough to scatter light (which is why some colloids appear cloudy), but small enough not to settle under gravity.

• Solutions: Particle size < 1nm
• Colloids: Particle size 1nm - 1000nm
• Suspensions: Particle size > 1000nm

Suspensions, on the other hand, have noticeably larger particles that can often be seen unaided.
These particles tend to settle out over time due to gravity.
Understanding particle size helps not only in identifying the type of mixture but also in predicting its behavior and how it can be separated.
For example, suspension particles will eventually settle, making them easier to filter out compared to colloids and solutions.