gibb free energy❤️

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.

Which of the following would most likely lead to a spontaneous reaction.

• A high negative enthalpy.

• 
  A high positive enthalpy.

• 
  

  A low negative enthalpy.

• 
  

  A low positive enthalpy.

What are the best conditions to lead towards a spontaneous reaction?

• 
  high negative enthalpy, high temp, high negative entropy

• 
  high positive enthalpy, high temp, high negative entropy

• 
  high negative enthalpy, low temp, high positive entropy

• 
  high negative enthalpy, high temp, high positive entropy.

Entropy increases from solid, liquid to gas. Why?

• 
  Molecules are more energetic

• 
  Molecular randomness decreases

• Molecular disorder increases

• 
  Molecules are more reactive

Which sample has the lowest entropy?

• 
  1 mole of KNO₃(l)

• 
  1 mole of H₂O(l)

• 
  

  1 mole of KNO₃(s)

• 
  

  1 mole of H₂O(g)

Which phase change represents a decrease in entropy?

• 
  

  gas to liquid

• 
  solid to liquid

• 
  liquid to gas

• 
  

  solid to gas

The formation ½ A₂ + 2 B₂ + C --> CAB₄ has an enthalpy of formation of -104 kJ and a change in entropy of -60.8 J/K at 30 °C. What is the free energy and spontaneity of the reaction?

• 
  

  -18.3 kJ, not spontaneous

• 
  

  +85.6 kJ, not spontaneous

• 
  -85.6 kJ, spontaneous

• 
  +18.3 kJ, spontaneous

Predict the signs of ΔH , ΔS and ΔG for the reaction:

Mg(s) --> Mg(g)

• Δ H = + , Δ S = + and Δ G = - (At high temperature)

• Δ H = + , Δ S = + and Δ G = - (At all temperature)

• Δ H = - , Δ S = + and Δ G = - (all temperature)

  Δ

• Δ H = + , Δ S = + and Δ G = - (At low temperature)

Given the following information, calculate ΔG⁰ for the reaction below at 25⁰C: (K = ⁰C + 273)

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