AP Chem Thermodynamics Practice

Front

Free energy change at equilibrium is...

Back

Zero

Front

For a reaction to be spontaneous under standard conditions at all temperatures, the signs of ΔHΟ and ΔSΟ must be __________ and __________, respectively.

Back

-, +

Front

Thermodynamically unfavorable reactions...

Back

occur only with a sustained energy input

Front

The entropy will usually increase when

Back

all of these (a molecule is broken into two or more smaller molecules, a reaction occurs that results in an increase in the number of moles of gas, a solid changes to a liquid)

Front

As a sample of solid iodine sublimes, the entropy of the sample

Back

increases because the particles are more randomly arranged

Front

Define enthalpy (ΔH).

Back

The heat content of a system at constant pressure.

Front

What is the second law of thermodynamics?

Back

The total entropy of an isolated system can never decrease over time.

Front

What does a negative ΔG indicate?

Back

The reaction is spontaneous.

Front

What is the relationship between ΔH and ΔS for a spontaneous reaction at high temperatures?

Back

ΔH must be negative and ΔS must be positive.

Front

What is the significance of standard conditions in thermodynamics?

Back

Standard conditions refer to a set of specific conditions (1 atm pressure, 25°C) used for measuring and comparing thermodynamic properties.