Gibbs Free Energy

The equation that relates enthalpy, temperature and entropy is

• Hess's Law

• Second Law of Thermodynamics

• Gibbs Free Energy

• Calorimetry

What does Gibbs Free Energy tell us?

• How much energy is given off by a reaction.

• The tendency of a reaction to become "random"

• How spontaneous a reaction is.

What information do we need to perform a calculation of Gibbs Free Energy?

• Enthalpy of the reaction.

• Entropy of the reaction.

• The temperature of the reaction in Kelvin.

• All of the above are needed.

Given the following information, calculate ΔG⁰ for the reaction below at 25⁰C: SnCl₄(l) + 2 H₂0(l) → SnO₂(S) + 4HCl(g), ΔH⁰=133.0 kJ and ΔS⁰ =401.5 J/K

• -252.6 kJ

• -13.4 kJ

• 13.4 kJ

• 252.6 kJ

Tags

NGSS.HS-PS3-1

For a reaction to be spontaneous under standard conditions at all temperatures, the signs of ΔH^Ο and ΔS^Ο must be __________ and __________, respectively.

• +, +

• +, -

• -, +

• -, -

• +, 0

Which combination of ΔH and ΔS NEVER has a spontaneous reaction?

• +ΔH and +ΔS

• +ΔH and -ΔS

• -ΔH and -ΔS

• -ΔH and +ΔS

At what temperature would a given reaction become spontaneous if ΔH =+119kJ and ΔS=+263J/K.mol

• 452 K

• 2210 K

• 382 K

• 363 K

What is the Gibbs Free Energy equation?

Which of the following best describes Gibbs Free Energy?

• The energy available to do work in a system

• The total energy of a system

• The energy lost as heat in a system

• The energy stored in chemical bonds

• The reaction is non-spontaneous

• The reaction is at equilibrium

• The reaction is spontaneous

• The reaction is endothermic