Heat & Temperature
The average amount of kinetic energy per particle contained in an object is the object's __________
Temperature
Name the three states of matter, in order from HIGHEST to LOWEST temperature.
Gas, liquid, solid.
Calculate the heat required to raise 100 g of water from 20°C to 30°C. (Use c=4.18 J/g°C)
4180 J
Boyle's Law states that ______ and ______ are inversely proportional if temperature is held constant.
Pressure, Volume
Theory: "Energy cannot be created or destroyed. The change in internal energy of a system equals the heat added to the system minus the work done by the system." Which law is this?
First Law
_________ is the amount of energy transferred between objects due to a temperature difference.
Heat
The melting/freezing point of water is ____ degrees Celsius, and the boiling point is ______ degrees Celsius.
0, 100
Calculate the heat required to raise 200 g of aluminum (c = 0.897 J/g·°C) from 20°C to 100°C (numeric).
Q = (200 g)(0.897 J/g·°C)(80°C) = 14,352 J.
Charle's Law states that if pressure is held constant, then Volume and Temperature are _____ proportional.
directly
"Heat spontaneously flows from a hotter object to a colder one; in an isolated system, the total entropy tends to increase over time." Which law is this?
Second Law
If a hot object transfers energy to a cold object, heat will flow until they reach __.
Thermal equilibrium or the same temperature
Heat of Fusion is the amount of energy needed to _____ or _______ a substance.
Melt, freeze
Calculate the heat required to vaporize 200 g of water at 100°C. (Use Hv=2260 J/g).
452000 J
Convert 100ºC into Kelvin
373
Explain why bridges and sidewalks include joints in terms of thermal expansion.
Joints accommodate cumulative ΔL across spans and prevent buckling/cracking.
Name a temperature scale that can never be negative.
Kelvin Scale (or Rankine Scale)
Heat of Vaporization is the amount of energy needed to _____ or ______ a substance.
Condense, Vaporize
A balloon has volume 2.0 L at 20°C. If temperature rises to 80°C at constant pressure, what is the new volume?
T1 = 293 K, T2 = 353 K; V2 = 2.0 × (353/293) ≈ 2.41 L.
If you squeeze a balloon to one quarter of its original volume, the pressure inside will _______ by a factor of _________.
increase, four
State the Zeroth Law of Thermodynamics in one sentence and give a simple classroom example.
If A is in thermal equilibrium with B and B with C, then A with C. Example: thermometer calibrated in ice/water matches beaker temp.
Q = mcΔT
Define each symbol and its units.
Q = mcΔT (Q is heat in J, m is mass in g, c is specific heat in J/gºC, ΔT is change in temperature °C).
When heat is added to water at its boiling point, what will happen to the temperature of the water and WHY?
it will remain the same... energy goes into breaking down bonds and/or making the phase change
Compute the total heat required to change 1000 g of ice at 0°C into steam at 100°C using HF = 334 J/g, c_water = 4.18 J/g·°C, HV = 2260 J/g (show steps and numeric total).
Q_melt = 1000×334 = 334,000 J; Q_heat = 1000×4.18×100 = 418,000 J; Q_vap = 1000×2260 = 2,260,000 J; Total = 3,012,000 J.
If the temperature of a gas is doubled, the volume will _____ by a factor of _______.
increase, 2
A 1.60 m rod at 21°C is heated to 84°C and lengthens by 1.7 mm. Calculate α (numeric).
α = 0.0017 m / (1.60 m × 63°C) ≈ 1.7×10^−5 1/°C.