P1.1 Heating and energy transfer (from AQA) Flashcards
“The particles of solids, liquids, and gases all have the same amount of energy because they are all particles”
TRUE OR FALSE? Explain.
FALSE because
Name the four types of energy transfer that involve particles
- Conduction
- Convection
- Evaporation
- Condensation
Use the kinetic theory to explain the arrangement of particles in a solid (3)
- In fixed positions
- Vibrate around fixed positions
- So solid keeps it’s shape
Use the kinetic theory to explain the arrangement of particles in a liquid (2)
- In contact with each other
- Move at random
Use the kinetic theory to explain the arrangement of particles in a gas (4)
- Move at random
- Much faster
- Further apart
- Less dense
Which state of matter has the highest amount of energy and which has the least?
Gas has most
Solid has least
What is the role of free electrons in a metal? (3)
- HOLD the +ve metal ions together
- MOVE at random inside conductor
- TO CONDUCT
A metal rod is heated at one end. How is the heat passed to the other end of the metal? (3)
- Free electrons at hot end GAIN Ek
- They DIFFUSE and collide w/ COOLER and ions
- TRANSFER Ek to them
How do you increase the rate of evaporation? (3)
- Inc. SA
- Inc. temp
- Create a draught of air across the liquid’s surface
How do you increase the rate of condensation of vapour on a surface? (2)
- Inc. SA
- Reduce the surface’s temp
What does the rate at which an object transfers energy by heating depend on? (3)
- SA and V
- Material and SHAPE that the object is
- Nature of the SURFACE that the object’s in contact with
A desert fox has large ears to help keep it cool. How do large ears do this?
Bigger SA, more blood flow, more ENERGY TRANSFER
The rate at which energy is transferred by heating can be increased by… (1)
…a bigger temp difference between object and surroundings
What do U-values measure?
How effective a material is as an INSULATOR
The lower the U-value…
…the better the material is as an insulator
