Which of the following reactions will have 1:*lot0t4b s sunddw :the greatest decrease in entropy?

  Which of the following combinationsv ld 3m djk/-h*hzd 81whdmk 6gu4zi6gv7 -f:z of ΔH and ΔS results in the most spontaneous reaction at 2k hwmg3dgu8hi d1/z z4k6mf--*v:ldzj7 hvd6 98 K?

  Which of the following statements about entropy is incovr*ww 49za+ics t,e1)ehfey 7rrect?

  Which of the following compounds are arranged in order of decreasing entropyfg4nq.4 + sz-8mcmjzsr5u+ g w?

$C$(s)
$H_2O$(l)
$O_2$
$CO_2$(g)
>

  Which statement is true for an endothermic rvqh+hb1qi5 ;x; j w9swm7o6vfaus8e3 eaction that results in an increase in eh sxm9afi6ebj1;5 hw3u v8woq+vq s7; ntropy?

  Which statement about the relationship between Gibbs ykv1m nk)8 hn(o g. f0wuhkw87free energy change and the equilibrium cfy og)h .k8(km1hu7vk n8w 0wnonstant is correct?

  Which of the following factors affect the entropy of a system conx dg2)l1llh i(taining gases? 1 l(ld2 ig)hlx
I. The temperature of the system
II. The states of the system
III. The pressure of the system

  The Gibbs free energy change can be used to determ+7mn g,- avud9p0vsa+xyp8 dline the spontaneity of a reaction.- 0u pvldn9g+madaypv7,8s+ x
1.1.Define Gibbs free energy change of formation.
1.2.Define spontaneous reaction.

2.1.State a correctly balanced equation that represents the complete combustion of butane.

2.2.Using section 12 (Section 13- 2025 Syllabus) of the data booklet, calculate the Gibbs free energy change of this reaction.
ΔG$_{reaction}$=-  kJ mol$^{-1}$
2.3.State, with a reason, whether this reaction is spontaneous or not.

Important note: The section numbers mentioned in the video solution are specific to the 2024 syllabus.
You can refer to the question stem to find the section numbers in the 2025 syllabus.

  Methanol is produced by reacting carbon monox7zlln) gko( c6ide and hydrogen according to the fogll n(kz7c) 6ollowing reaction:
$CO(g)$+2$H_2(g)$ → $CH_3OH$(g)
$CO(g)$+2$H_2(g)$ ← $CH_3OH$(g)
1.Deduce the equilibrium constant expression for the formation of methanol.
At 500$^{\circ}C$ ,a 750cm$^3$ sealed flask is found to contain 0.923 mol of CH_3OH, 0.352mol of CO and 0.124 mol of $H_2$.
2.1.Calculate the value of K$_c$ at 500 $^{\circ}C$. K$_c$=  
2.2.Using sections 1 and 2 of the data booklet, calculate ΔG$^θ$ at 500 $^{\circ}C$.
T=  K;ΔG$^θ$=-  kJ mol$^{-1}$

  Ethanol can be produced through the 2mav,a 8do h )a1:xilsfermentation of glucose:
$C_6H_12O_6$(aq)→2$C_2H_5OH$(l)+2$CO_2$(g)
1.1.Predict whether the entropy change for this reaction is positive or negative. Explain your reasoning.
1.2.The absolute entropy for glucose is +209.2 J K$^{-1}$ mol$^{-1}$.Using section 12 (Section 13- 2025 Syllabus) of the data booklet, calculate the entropy change for this reaction.
ΔS$_{reaction}$=+  JK$^{-1}$ mol$^{-1}$

2.The enthalpy of formation of glucose is -1273.3kJ mol$^{-1}$.Using section 12 (Section 13- 2025 Syllabus) of the data booklet, calculate the enthalpy change for this reaction.
ΔH$_{reaction}$=-  kJ mol$^{-1}$

3.Using your answers to (a)(ii) and (b), calculate the Gibbs free energy change at 298K.
ΔG=-  kJ mol$^{-1}$
Important note: The section numbers mentioned in the video solution are specific to the 2024 syllabus.
You can refer to the question stem to find the section numbers in the 2025 syllabus.

  Dry ice, solid $CO_2$,is commonly used as a cooling or freezing agent in the medical and food industries.
1.Write an equation representing the sublimation of $CO_2$.
2.The enthalpy of sublimation for $CO_2$ is +26.1kJ mol$^{-1}$ and the absolute entropy of $CO_2$ in the solid state is 51.1 J K$^{-1}$ mol$^{-1}$.
2.1.Using section 12 (Section 13- 2025 Syllabus) of the data booklet, calculate the entropy change associated with the sublimation of $CO_2$.
ΔS$_{reaction}$=+  J K$^{-1}$ mol$^{-1}$
2.2.Using your answer to (bi), calculate the Gibbs free energy change for the sublimation of $CO_2$ at K.
ΔG=-  kJ mol$^{-1}$

3.Calculate the minimum temperature at which $CO_2$ sublimates.
T＞  K

Important note: The section numbers mentioned in the video solution are specific to the 2024 syllabus.
You can refer to the question stem to find the section numbers in the 2025 syllabus.

  How does Gibbs free energy relate to chemical equilix2k q-uqr g6b*brium?

  Consider the following reaction:7e4c c rx-cikx oq+x+3
$C_2H_4$(g)+$H_2$(g)→$C_2H_6$(g)
ΔH is -136kJ mol$^{-1}$
ΔS is -121jk$^{-1}$ mol$^{-1}$
ΔG at 298K is -99.9kJ mol$^{-1}$
1.1.Explain why the enthalpy of formation of $H_2$ is 0 kJ mol$^{-1}$.
1.2.Explain why the entropy change for this reaction is negative.

2.Explain how a reaction can be spontaneous with a negative entropy change.

3.Calculate the temperature at which this reaction is no longer spontaneous.
T=  K

  The following graph 6r vab.2c0 od(4qzuj(o kx ya-shows the Gibbs free energy against the extent of reaction for a reversible reaction 0d-b roa2jcx yuoa (v.z46q(k.
At what point is the reaction at equilibrium?