GoConqr has a new look! Let us know what you think.

Sign up free

Flashcards

Thermodynamics

Tamika Demiyah Physics Year 11 English 37 cards

Thermodynamics

Cards in this deck (37)

  1. 1What is the thermal/ internal energy of a substance?All substances have internal energy
    Int. En. is the sum of kinetic & potential energies of the substance's molecules    What is the thermal/ internal energy of a substance?
  2. 2Formula for internal energyInternal Energy = Ep + Ek
    where Ep is potential energy (energy in bonds between molecules & energy held in nuclei of atoms) & Ek is Kinetic Energy of particles
  3. 3Under what conditions do changes in temperature occur but state of substance is constant?Internal Energy = Ep + Ek
    Changes in temperature occur when Ek changes, due to the heating or cooling of a substance
  4. 4Under what conditions does a phase change in a substance occur but temperature of substance is constant?Internal Energy = Ep + Ek
    Change in phase (solids, liquids, gases) occurs when the potential energy/ or the molecular bonds between particles of a substance become weaker or stronger
  5. 5What is the relationship between the changes in Ep and the changes between states of matter?Solid -> Liquid
    increase in Ep
    Liquid -> gas
    increase in Ep
    But, gases of 0 Ep
  6. 6What is special about the internal energy of gases?Inter-molecular bonds do not exist in gases
    Hence, there is 0 Ep and energy is entirely made of Ek
  7. 7What is heat?Heat is the transfer of energy from higher temp. to low temp.
  8. 8How does heat affect a substance? Hint: consider Temp., Ek and Inteneral energySubstance absorbing heat
    Increase in Temp., Ek & Internal Energy
    Substance releasing heat
    Decrease in Temp., Ek & Internal Energy
  9. 9Define temperatureTemperature is a measure of the average Ek of a substance
  10. 10What is Thermal Equilibrium and how is it achieved?Thermal Equilibrium: when there is no net change in temperature between 2 objects in contact. i.e. no heat transfer & objects are at the same temp.What is Thermal Equilibrium and how is it achieved?
  11. 11Explain the Zeroth LawWhen A is in thermal equilibrium with B, and B is in thermal equilibrium with C, then C is in thermal equilibrium with AExplain the Zeroth Law
  12. 12Types of temperature scales.1. The Kelvin Scale - starts from absolute zero (particles have 0 Ek)
    2. Celsius Scale - based on O degrees celsius (freezing pt. of water)    Types of temperature scales.
  13. 13Convert 0 degrees celsius to Kelvin0 degrees = 0 degrees + 273 Kelvin = 273 K
  14. 14Convert 0 Kelvin to degrees celsius0 K = 0 K - 273 degrees celsius = -273 degrees
  15. 15How to convert between Kelvin and Degrees CelsiusKelvin -> Degrees Celsius
    - 273 to the kelvin
    Degrees Celsius -> Kelvin
    + 273 from degrees celsius
  16. 16What is the Specific Heat Capacity of a substance?The S.H.C is the energy required to increase the temperature of a 1kg substance by 1 degrees celsius/ kelvin without changing state
  17. 17Substances A and B are absorbing energy at the same rate and substance A increases by 1 degrees celsius first. What does this tell us about the S.H.C of the substances.Substance B has a higher S.H.C since it requires more energy than substance A to increase its temperature.
    Meanwhile, substance A has a lower S.H.C since it requires less energy to increase its temperature.
  18. 18Formula for Specific Heat CapacityFormula for Specific Heat Capacity
  19. 19Mass and Volume equivalence of water1mL = 1 g
    1000mL = 1000g = 1L = 1kg
  20. 20What is a calorimeter and how does it work?A device used to find the S.H.C of a substance
    Heated objected placed in thermally isolated container containing a known amount of water. Object & liquid reach thermal equilibrium & final temp. is used to determine the S.H.C of the object.    What is a calorimeter and how does it work?
  21. 21Explain Latent HeatThe energy required to change the state of a substance i.e. weaken/ break inter-molecular forces without changing the temperature of the substance
    It is a change in Ep not Ek
  22. 22Explain Latent Heat of Fusion + formulaThe energy required to convert 1kg of a solid into liquid without changing the temperatureExplain Latent Heat of Fusion + formula
  23. 23Explain Latent Heat of VaporisationThe energy required to convert 1kg of a liquid substance to gas without changing its temperatureExplain Latent Heat of Vaporisation
  24. 24—
  25. 251st Law of Thermodynamics Hint: Conservation of Energy1st Law of Thermodynamics Hint: Conservation of Energy
  26. 262nd Law of ThermodynamicsAs energy is transferred, the quality of the energy gets worse. i.e. the natural tendency of a system to degenerate into a more disordered state, this is known as "entropy"
    "Entropy" - a measure of the molecular disorder of s system
  27. 27Explain the image in terms of the 2nd Law of ThermodynamicsAs ice melts, its molecules become more disordered, hence entropy increases. The molecules of the melted ice has a natural tendency to remain in this disordered state, therefore it cannot freeze back into a perfect cube. Hence, entropy never decrease.Explain the image in terms of the 2nd Law of Thermodynamics
  28. 28The Ideal Gas LawThe Ideal Gas Law
  29. 29Explain the effects of temperature on an object.As the temperature increase, Ek of molecules increase and vibrate faster. Rapid vibrations cause increase in pressure which cause the substance to expand/ increase volume until pressure is neutralised.Explain the effects of temperature on an object.
  30. 30The relationship between variables of the Ideal Gas LawPV = nRT
    Pressure and volume is directly proportional to temperature
    Volume is inversely proportional to pressure
    Pressure is inversely proportional to volume
  31. 31Interpret the following graphSubstance T1 has a lower temperature since the majority of its molecules have a smaller Ek than the molecules of T2
    Substance T2 have a greater number of molecules that have enough Ek to escape from liquid    Interpret the following graphInterpret the following graph
  32. 32What is the difference between boiling and evaporisation?Evaporisation occurs on the surface of a liquid when it changes to gas.
    Boiling occurs when all the particles in a liquid is heated up.    What is the difference between boiling and evaporisation?
  33. 33Define ConductionThe transfer of thermal energy from atom/ molecule to another in direct contact
    Good conductors of electricity = good conductors of heat    Define Conduction
  34. 34Why are solids better conductors of heat than liquids or gases?Molecules in solids are closer than in liquids and gases. Hence, vibrations between molecules transfer heat quicker
  35. 35Define RadiationElectromagnetic waves that is emitted by warm/ hot objects and can be absorbed by another object.
    e.g. UV light from sun, heat from stove, x-rays    Define Radiation
  36. 36Define ConvectionThe movement of heated molecules, heating other molecules around it
    Applies only to liquids and gases    Define Convection
  37. 37How heaters workHow heaters work

Information

Description
Year 11 Physics Flashcards on Thermodynamics , created by Tamika Demiyah on 16/11/2018.
Created by
Tamika Demiyah
Views
0
Rating

Feedback

What is it about?

What do you think of the new look?

How do you like it?