5.1 Thermal Physics Flashcards
(38 cards)
How do you convert between Celsius and Kelvin?
temperature in K = temperature in °C + 273
What is specific latent heat of vaporisation?
The amount of energy needed to change a substance from liquid to gas without a change in temperature.
What happens to air particles as temperature increases?
The average velocity of the molecules increases.
What is absolute zero?
The lowest possible temperature, defined as 0 K or -273 °C.
Define pressure in terms of force and area.
Pressure is the average force per unit area.
What is Brownian motion?
The random motion of small particles suspended in a fluid.
What is the formula for calculating specific latent heat?
E = mL, where L is the specific latent heat.
What occurs when two objects at different temperatures are in thermal contact?
Thermal energy will pass from the hotter to the cooler object until thermal equilibrium is reached.
What does the specific heat capacity of a substance represent?
The amount of energy needed to raise the temperature of 1 kg of the substance by 1 K.
Fill in the blank: The energy transferred during a change of state is calculated using _______.
E = mL
What is the relationship between temperature difference in Celsius and Kelvin?
A temperature difference of 1 °C is equal to 1 K.
What is the kinetic theory model of ideal gases based on?
The assumption that gas particles are in constant random motion and that all collisions are perfectly elastic.
What happens to the internal energy of a substance when it is heated?
The internal energy increases.
True or False: The particle model explains why gases can be compressed while solids cannot.
True
What is the formula for electrical energy supplied to a heater?
E = IVt, where I is the heater current, V is the heater voltage, and t is the heating time.
What does thermal equilibrium mean?
Two objects or materials are at the same temperature and no thermal energy flows between them.
What is the significance of specific melting and boiling points for pure substances?
Pure substances change state at specific melting and boiling points.
Fill in the blank: The internal energy is the sum of the ______ and ______ energies of the molecules in a system.
kinetic, potential
What is the relationship between the internal energy of an ideal gas and its temperature?
The internal energy of an ideal gas is proportional to its temperature in kelvin.
What is the equation that relates the average kinetic energy of gas particles to temperature?
KE = kT, where k is the Boltzmann constant.
What is the value of the Boltzmann constant?
k = 1.38 × 10^-23 J K^-1.
What is the ideal gas equation?
PV = nRT.
What does ‘n’ represent in the ideal gas equation?
n = amount of gas in moles (mol).
What is the value of the molar gas constant R?
R = 8.31 J mol^-1 K^-1.
