Problem 9 - Chemistry: The Central Science

Question

List the three states of matter in order of (a) increasing molecular disorder and (b) increasing intermolecular attraction. (c) Which state of matter is most easily compressed?

Step-by-Step Solution

Answer

(a) The order based on increasing molecular disorder is: solid, liquid, gas. (b) The order based on increasing intermolecular attraction is: gas, liquid, solid. (c) The gas state is the most easily compressed state of matter.

Step 1: (a) Increasing molecular disorder

To list the states of matter in order of increasing molecular disorder, think about the arrangement of molecules in each state: 1. Solid state: Molecules are arranged in a well-ordered and fixed pattern, with low molecular disorder. 2. Liquid state: Molecules are less ordered than in the solid state but more ordered than in the gaseous state, with moderate molecular disorder. 3. Gas state: Molecules are randomly arranged and have no fixed pattern, with high molecular disorder. So, the order based on increasing molecular disorder is: solid, liquid, gas.

Step 2: (b) Increasing intermolecular attraction

To list the states of matter in order of increasing intermolecular attraction, consider the forces between molecules in each state: 1. Gas state: Molecules are far apart, with minimal intermolecular attraction. 2. Liquid state: Molecules are closer together than in the gas state, with moderate intermolecular attraction. 3. Solid state: Molecules are tightly packed in a fixed pattern, with strong intermolecular attraction. So, the order based on increasing intermolecular attraction is: gas, liquid, solid.

Step 3: (c) Most easily compressed state of matter

The most easily compressed state of matter would be one in which molecules are far apart and have the least intermolecular attraction, allowing them to be pushed closer together more easily. Based on this criterion, the gas state is the most easily compressed state of matter.

Key Concepts

Molecular Disorder and States of Matter

In understanding molecular disorder, let's first imagine how molecules are organized in each state of matter.
In a solid state, molecules are arranged in a specific, fixed pattern almost like a tightly packed army. They have very little room to move around, resulting in low molecular disorder.
On the other hand, in the liquid state, molecules enjoy a bit more freedom. They are still close to each other but not as arranged as in solids, making them more disorderly. Think of a jigsaw puzzle that's been shifted just enough for the pieces not to fit perfectly anymore.
Then, there are gases. Here, molecules are like chaotic party guests, bouncing around with no specific path or arrangement. This randomness gives gases high molecular disorder.
So, to sum it up:

• Solids come first with the least molecular disorder.
• Liquids are next, being moderately disorderly.
• Gases top the list with the most disorder.

Intermolecular Attraction in Each State

Intermolecular attraction is about how strongly molecules pull each other. This "pull" is something like gravity, where molecules want to stick together.
In gases, molecules are spread out and barely interact. They are like distant friends who rarely keep in touch, so the attraction is minimal.
In liquids, molecules are closer, mingling but with some personal space. They are like acquaintances at a networking event, with a medium level of attraction.
For solids, this attraction is strongest. Molecules stick close together, forming a tight bond akin to family members gathered around a dinner table.
The order of increasing intermolecular attraction is:

• Gases, with the least attraction.
• Liquids, with moderate attraction.
• Solids, having the highest attraction.

Compressibility of Different States

When we think about compressibility, we're asking how easily we can squash molecules closer together. The more space between molecules, the easier it is to compress them.
Gas states excel at this. Imagine trying to pack a suitcase with clothes that are just lying around; they compress easily.
In contrast, liquids are not as compressible. Picture squeezing a water balloon. It gives a little, but most of the water stays in place.
Solids are the most stubborn when it comes to compression. Think of trying to squish a rock; it barely gives any space.
So, in terms of compressibility:

• Gases are the most compressible.
• Liquids can be compressed to a small extent.
• Solids are the least compressible.