Which of the following reactions will have the q2hza ;si 0tx 83zvm*z;/sjw lgreatest decrease in entropy?

  Which of the following combinations of ΔH and ΔS results in the jkxm- y 7q/.nmmost spontaneous 7 /qnyxmj-m.kreaction at 298 K?

  Which of the following statements about entropy is in9dvq5 b0 fpys3- bdpmb9ku 50ecorrect?

  Which of the following compounds are arranged in order /no)+jkm66.zgpp8ch ge) jw y of decreasing entropy?

$C$(s)
$H_{2}O$(l)
$O_2$
$C{O}_2$(g)
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  Which statement is true for an endothermic reaction.8z0 x(c nfvdg/f2z uv that results in an increase in entroduxf 0nz.28 fc(/g zvvpy?

  Which statement about the relationship between Gidm,:a - 6rtskybbs free energy change and the equilibrium constant is corrk-6tdm rs: ,ayect?

  Which of the following factorslafwf*-mkkpv 2/j ; 5;) hkolh affect the entropy of a system containing gases? h/ l f;fjak2vmh*k5l)k;-w po
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 determine the9+t( cvdbj ;3y/7 agz/ cjc:n3phq9qmouli r6 spontaneity of a react(z r3vutimqcqdpn/63;7bg:cj h+9y ajlc o9 / ion.
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 monoxide and hydrogen according to the fhm of- e77cf f.2+)kw;rujmp) exv7)bnej4ugollowinmmfpunu 7 h-j27e .exw7r)o4)+cv)kf;eg fbjg reaction:
$CO(g)$+2$H_2(g)$ → $C{H}_{3}OH$(g)
$CO(g)$+2$H_2(g)$ ← $C{H}_{3}OH$(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${}^{\theta }$ at 500 ${}^{\circ }C$.
T=  K;ΔG${}^{\theta }$=-  kJ mol${}^{-1}$

  Ethanol can be produced through the fermentation of glucosev)n ypk037d nx:
$C_6{H}_{1}2O_6$(aq)→2$C_2{H}_{5}OH$(l)+2$C{O}_2$(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 $C{O}_2$,is commonly used as a cooling or freezing agent in the medical and food industries.
1.Write an equation representing the sublimation of $C{O}_2$.
2.The enthalpy of sublimation for $C{O}_2$ is +26.1kJ mol${}^{-1}$ and the absolute entropy of $C{O}_2$ 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 $C{O}_2$.
ΔS${}_{reaction}$=+  J K${}^{-1}$ mol${}^{-1}$
2.2.Using your answer to (bi), calculate the Gibbs free energy change for the sublimation of $C{O}_2$ at K.
ΔG=-  kJ mol${}^{-1}$

3.Calculate the minimum temperature at which $C{O}_2$ 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 en ,ah1ds*p ;x6gppphrk 46gj+dergy relate to chemical equilibrium?

  Consider the following re7ustp y5v i8.p+heb;z action:
$C_2{H}_4$(g)+$H_2$(g)→$C_2{H}_6$(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 shows the Gibbs free energy against the edmd) sttj70, kxtent of reaction for a ret)jk ,tmsd 70dversible reaction.
At what point is the reaction at equilibrium?