Particles, Compression And Diffusion

Explanation
Soldiers standing in rows can represent a solid because solids have a definite shape and volume, just like the soldiers standing in a structured formation. They are closely packed together and maintain their positions, similar to how solid particles are closely packed and have strong intermolecular forces that keep them in place.

Explanation
Solid particles have the smallest amount of energy compared to liquid and gas particles. In a solid, the particles are closely packed together and have the least amount of movement. They vibrate in fixed positions, resulting in lower energy levels. In contrast, liquid particles have more energy as they are more loosely packed and can move around each other. Gas particles have the highest energy levels as they are the most spread out and can move freely in all directions. Therefore, solid particles have the smallest amount of energy.

Explanation
Solids and liquids cannot be compressed because the particles are already tightly packed and close together. In solids, the particles are arranged in a fixed pattern and have very little space to move. In liquids, although the particles are not arranged in a fixed pattern, they are still closely packed and have minimal space between them. Therefore, any attempt to compress solids or liquids would require the particles to be pushed even closer together, which is not possible due to their already close proximity.

Explanation
Diffusion is the process by which particles move from an area of high concentration to an area of low concentration. This movement occurs until the concentration of particles is equalized or balanced. Therefore, the correct answer is "Particles move from where there are a lot to where there are fewer."

Explanation
Melting refers to the process in which a solid substance changes into a liquid state. This occurs when the temperature of the solid is raised to its melting point, causing the particles to gain enough energy to overcome the forces holding them together in a solid structure. As a result, the solid's rigid arrangement breaks down, and it transforms into a more fluid and less organized liquid state.

Explanation
Potassium permanganate is a strong oxidizing agent that can react with various substances, including organic matter and certain chemicals, causing a change in color. In this case, when potassium permanganate crystals are added to water, they dissolve and release manganese ions, which react with water molecules to form a purple-colored compound. Therefore, the presence of potassium permanganate crystals is responsible for turning the water purple. Sodium chloride and potassium chloride do not have the same oxidizing properties and would not cause a color change in water.

Explanation
Sound travels faster in water than in air because the particles in water are closer together compared to the particles in air. In a denser medium like water, sound waves can propagate more quickly as the particles can transmit the vibrations more efficiently. This is why sound travels faster in water.