AP Chemistry Unit 9

Entropy is always ________ in the Universe

• increasing

• decreasing

• constant

Tags

NGSS.HS-PS3-4

Which has the HIGHEST entropy change?

• 1 --> 2 particles

• gas --> liquid

• solid --> gas

• low to high temperature (same phase)

Which has a negative sign for S?

• water evaporating

• NaCl dissolving in water

• water freezing

• sublimation of CO2

Which has a positive sign for S?

• 2Na (s) + Cl2 (g) --> 2NaCl (s)

• H2O (g) --> H2O (l)

• H+ (aq) + NO3- (aq) --> HNO3 (l)

• CaCl2 (s) --> Ca2+ (aq) + 2Cl- (aq)

reaction is ALWAYS spontaneous

• - H, - S

• + H, + S

• + H, - S

• - H, + S

Tags

NGSS.HS-PS1-4

a reaction that is exothermic and has a decrease in entropy is

• spontaneous at high temps

• spontaneous at low temps

• always spontaneous

• never spontaneous

Tags

NGSS.HS-PS1-5

enthalpy is driving force when

• exothermic

• endothermic

• increase in entropy

• decrease in entropy

Tags

NGSS.HS-PS1-4

entropy is the driving force when

• exothermic

• endothermic

• entropy increasing

• entropy decreasing

If a reaction occurs, then delta G is

• negative

• positive

• can't tell

• 0

Tags

NGSS.HS-PS1-4

An endothermic reaction that experiences an increase in entropy is

• always spontaneous

• never spontaneous

• spontaneous at HIGH temps

• spontaneous at LOW temps

Tags

NGSS.HS-PS1-5