A3.0 3.0- Explaining The Properties of Liquids & Gases Using The Particle Model Of Matter

What is viscosity?

Viscosity is how fast or slow a fluid flows. It depends on the resistance (friction) between the particles.

What does high viscosity mean?

The fluid is thick (like honey), flows slowly, and has more particle friction.

What does low viscosity mean?

The fluid is thin (like water), flows quickly, and has less particle friction.

How does the Particle Model explain high viscosity?

Particles are close together with strong forces, making it harder for them to move.

How does the Particle Model explain low viscosity?

Particles are farther apart with weaker forces, making it easier to move.

What happens to viscosity when a fluid is heated?

Particles move faster → Flow is easier → Lower viscosity

What happens to viscosity when a fluid is cooled?

Particles move slower → Flow is harder → Higher viscosity

Which flows faster: hot or cold liquid?

Hot liquid flows faster (it has lower viscosity).

What happens to a fluid at cold temperatures?

The fluid becomes thicker and moves slower because particles stick together and create more friction.

What happens to a fluid at hot temperatures?

The fluid becomes thinner and flows faster because particles move quickly and don't stick together as much, reducing friction.

What does density refer to?

Density is how much matter is packed into a certain space, which tells us how compact the particles are.

What happens if an object is denser (heavier) than the liquid?

It sinks because the object is heavier and its particles are more tightly packed than the liquid.

What happens if an object is less dense (less heavier) than the liquid?

It floats because the object is lighter and its particles are less tightly packed than the liquid.

Which state of matter is usually the most dense?

Solids, because their particles are tightly packed together in a small space.

Which state of matter is the least dense?

Gases, because their particles are spread far apart and take up more space

What makes a substance more dense?

The more particles packed into a certain volume, the denser the substance is.

Why is liquid water denser than ice?

Because ice has a special structure where the particles are spread out with more empty space.

What happens to water particles when it freezes?

The particles lock into a solid structure with more empty space between them.

What happens to density when temperature increases?

Density decreases because particles move faster and spread apart.

What happens to density when temperature decreases?

Density increases because particles slow down and get closer together.

What does the Particle Model of Matter say about temperature and particles?

Higher temperature = faster particles, more space.
Lower temperature = slower particles, closer together.

How are concentration, density, and viscosity related?

They are directly connected—higher concentration = higher density = higher viscosity.

What is concentration?

Concentration is the amount of solute (like sugar or salt) dissolved in a solvent (like water).

What does high concentration mean?

t means there is a large amount of solute in the solvent. Example: 5 scoops of sugar in one cup of tea.

What does low concentration mean?

It means there is a small amount of solute in the solvent. Example: 1 scoop of sugar in one cup of tea.

How can you tell a solution is more concentrated?

It may look darker, taste stronger, or feel thicker.

What is Buoyancy?

Buoyancy is the upward force that a fluid (like water) exerts on an object placed in it. It pushes against gravity. (Buoyancy is the ability of an object to float when placed in a fluid (like water, oil, or air).

What happens when an object sinks?

It means the object is denser than the fluid, and gravity is stronger than the buoyant force.

What happens when an object floats?

It means the object is less dense than the fluid, and the buoyant force is strong enough to fight gravity.

What two forces affect floating and sinking?

• Gravity: pulls objects down.

• Buoyant Force: pushes objects up.
  Whichever is stronger determines if the object sinks or floats.

What is Positive Buoyancy?

The object floats to the top because the buoyant force is stronger than gravity.
Example: A beach ball in a pool.
(Gravity < Buoyant Force)

What is Neutral Buoyancy?

The object stays in the middle of the fluid, neither floating nor sinking.
This happens when gravity and buoyant force are equal.
Example: A fish hovering still in water.
(Gravity = Buoyant Force)

What is Negative Buoyancy?

The object sinks because gravity is stronger than the buoyant force.
Example: A rock dropped into a pond.
(Gravity > Buoyant Force)

What is a Plimsoll Line on a ship?

It's a mark on the side of a cargo ship that shows how much weight the ship can safely carry without sinking. It changes depending on the season and type of water.

Why is the Plimsoll Line important?

It helps prevent ships from sinking by making sure they don’t carry too much weight.

Why do helium balloons float?

Helium is lighter and less dense than air, so the buoyant force pushes the balloon up.

How do hot air balloons float?

Heating the air inside makes it less dense than the cooler air outside, so the balloon rises.

How do blimps and zeppelins float in the air?

They are filled with gases like helium or hydrogen, which are less dense than air, allowing them to float and fly.

What is compression in fluids?

Compression is the pushing force on a fluid, which allows its particles to be moved or controlled, such as in spraying water from a hose or pumping air into a tire.

Can a solid be compressed?

Yes, but it's very difficult. Solids are tightly packed, so they need a lot of force to compress.

Which state of matter is easiest to compress?

Gas is the easiest to compress because its particles are spread out and have space between them, making them easier to push together.

In order of ease of compression, which states of matter are the most and least compressible?

Gas ➝ Liquid ➝ Solid, with gas being the easiest to compress and solid being the hardest.

Why are liquids and solids incompressible?

The particles in liquids and solids are already close together, so there is little space to compress them further.

What is pressure in fluids?

Pressure is the pushing force that fluids (like water or air) apply when they are squished or compressed.

What is the definition of pressure?

Pressure is how much force is applied to a certain area or space.

In which direction do fluids apply pressure?

Fluids apply pressure in all directions, not just one.

What happens when you dive deeper into water?

The deeper you go, the more water is above you, increasing the pressure on your body.

Why does pressure increase as you go deeper underwater?

The more water particles stacked above you, the more force (pressure) they apply on your body due to their weight.

What happens to pressure when the area increases?

Pressure decreases because the force is spread out over a larger area.

What happens to pressure when the force increases (and area stays the same)?

Pressure increases because more force is applied to the same space.