Applications of Thermodynamics
What is usually true about the entropy of solids compared to liquids and gases?
Solids have higher enthalpy than liquids and gases.
Solids are more miscible than liquids and gases.
Solids have equal entropy as liquids and gases.
Solids have lower entropy than liquids and gases.
What change occurs in the positional probability distribution (entropy) for particles confined within a harmonic oscillator potential well when temperature is increased while keeping particle mass and spring constant fixed?
Shift towards lower probability densities near equilibrium position as partitional contribution from rotational modes becomes relevant
Increased narrowing of positional probabilities due decreased reliance on vibrational states far from equilibrium
No change in positional probabilities since changes in kinetic energy do not affect confinement potentials
Increased broadening of positional probabilities due to higher kinetic energies allowing access to wider range of positions
During which process would you expect the entropy of a system to decrease?
Ice melting into water at 0°C.
Gas expanding into a vacuum.
A liquid solidifying into solid crystals lattice.
Water Vapor condensing into dew on a grass blade.
Which scenario best exemplifies an increase in entropy consistent with Gibbs free energy becoming negative under standard conditions?
Liquid water spontaneously freezing into ice below its freezing point while releasing heat into its surroundings.
Evaporation of ethanol at ambient pressure and temperature resulting from increased vapor pressure above its liquid form.
A hot piece of metal cooling down to room temperature by releasing thermal energy into its environment.
An exothermic reaction where reactants form products that occupy lesser volume than initial substances combined.
If mixing two ideal gases results in no volume change or heat transfer, which statement best describes the result concerning entropy?
There's no change in total entropy since ideal gases don't interact energetically when mixed.
The total entropy increases due to increased molecular randomness upon mixing.
The total entropy decreases as there’s no heat added during mixing.
Total entropy decreases due to decreased pressure after mixing occurs.
Which phase change is associated with a decrease in entropy?
Liquid evaporating to gas.
Solid melting into a liquid.
Gas condensing to a liquid.
Ice subliming into vapor.
What happens to entropy when a solid substance melts into a liquid?
It decreases
It fluctuates unpredictably
It stays the same
It increases

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In terms of molecular randomness, how does entropy change when salt dissolves in water?
Remain unchanged as salt simply dissociates
Fluctuates with temperature changes only
It increases due to greater dispersion of ions
Decrease due to interaction between poles decrease
Which factor, when increased, would result in the greatest decrease in entropy for a gaseous system at constant temperature?
Decreasing the volume of the container.
Introducing a catalyst that speeds up reaction rates.
Adding more gas molecules to the system.
Increasing the pressure by external means.
What happens to the entropy of a substance as it changes from solid to liquid?
It fluctuates unpredictably.
It remains constant.
It increases.
It decreases.