Science - States of matter Flashcards
What are the 3 states of matter
Solid, Liquid and Gas
Tell me the properties of a Solid
keep their shape, cannot flow, difficult to compress
Tell me the properties of a Liquid
keep their volume, take shape of container, difficult to compress
Tell me the properties of a Gas
change shape, spread out in all directions, easy to compress
What is diffusion
When gases or liquids mix without anything moving them, because particles move
around all the time
What is expansion
When materials expand (take bigger volume) when heated, because the particles vibrate more violently
What is contracting
When materials contract (take smaller volume) when cooled, because particles move
slower
P.S. The exception is water: water expands when frozen
What is Density
Density is the mass divided by the volume
When a material contracts, its density increases
When a material expands, its density decreases
Why do materials contract
Materials contract because particles move Slower
What does diffusion cause
Diffusion causes fluids to mix constantly
Are gases easy to compress
Gases are easy to compress
Are Solids easy to compress
No (You Can’t)
Are Liquids easy to compress
No (You can’t)
How do you calculate density
By dividing the mass of an object with its volume
What do we use to measure mass
We use an electronic balance to measure mass.
What are particles held together by
Particles are held together by forces, called bonds
Why is energy needed when solid changes to liquid
• When solid changes to liquid, energy is needed to break these bonds
what type of change is melting, freezing and evaporating?
• Melting, freezing, condensing etc. are physical changes
Why do solids expand when heated?
• Solids expand when heated – the particles vibrate more
How much is atmospheric pressure? (In pascal)
100,000 pascal
Why do we not feel the pressure of the air particles hitting our body?
• We do not feel the pressure, because the fluid inside our bodies exert pressure from inside.
The higher you go, the LOWER or HIGHER the pressure?
Lower
The Lower you go, the LOWER or HIGHER the pressure?
Higher
What are gases and liquids also known as?
Fluids
How do objects float
• When the two forces, upthrust and weight balance, the object floats
What is the density of water
• The density of water is 1g/cm3
What are the 2 factors effecting upthrust
• The factors affecting upthrust are density and depth of the liquid
Why do hot air balloons fly
• Hot air balloons fly because the overall density of the whole balloon is less than the air around it (balloon is very big)
Where does convection take place
• Convection takes place in fluids (liquids and gases).
Why do particles turn less dense when heated
• When part of a fluid is heated, the particles spread further apart and the fluid becomes less dense.
What are other names for drag
• Water resistance and air resistance are called drag
What is drag caused by
• Drag is caused by moving objects that are pushing particles out of the way
What objects have higher drag and what objects dont?
• Smooth objects have less drag while rough objects have more drag
What are streamlined objects shaped to have
• Streamlined objects are shaped to reduce drag. They have a smaller front area.
What does a smooth object moving at a steady speed have
• An object moving at a steady speed, has balanced forces
What will the force from the engine balance
• The force from the engine will balance drag and friction
What causes more drag
• The faster the object moves, the more the drag
