IB Chemistry Topic R1.4 Entropy and Spontaneity Questionbank (HL)

Question 1

HLPaper 1A

For a reaction where $Δ H > 0$ and $Δ S < 0$ , what is the sign of $Δ G$ at all temperatures?

Question 2

HLPaper 1A

Which of the following processes has a negative entropy change ( $Δ S$ )?

Question 3

HLPaper 1A

Which of the following is always true at equilibrium?

Question 4

HLPaper 1A

Which of the following physical states has the highest entropy at a given temperature?

Question 5

HLPaper 2

For a chemical reaction, the Gibbs free energy under non-standard conditions is given by:

$Δ G = Δ G^{\circ} + R T ln Q$

Where:

$Δ G^{\circ} = - 10 kJ mo l^{- 1}$

$T = 298 K$

$Q = 0.10$

$R = 8.314 \times 1 0^{- 3} kJ mo l^{- 1} K^{- 1}$

1.

Calculate the value of $Δ G$ under these conditions.

[3]

2.

Determine whether the reaction is spontaneous under these conditions.

[1]

3.

Explain what happens to the value of $Δ G$ as the value of $Q$ increases.

[1]

IB Chemistry R1.4 Entropy and Spontaneity Questionbank