Which of the following statements are cor/(f htim tmw-0rect?
I.Voltaic cells convert chemical energy into electrical energy
II.Electrolytic cells convert electrical energy into chemical energy
III.Electrolytic cells require a salt bridge

  Which of the following are the standard y8hfgbjp 9,go4gh5 u4conditions for standard cell potentials? 8b o4 gjh4yg5fu,9p gh
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is co3 0ptqm ekphh8*. ec)jrrect?

  Which row of the table is correct fog/)55xnzsb d3tjoakuf l;v ,3 r a spontaneous reaction?

  Which statement about electrochemical cells is not corre*:aw/ sy6h :pj,pus llct?

  What are the correct products of the reaction of nitric acid and)bgbw bq6:v2zthn1k 5/xqv9u9j :nerii 9lg) magnesium metale2 b v9t5h9u6ijkqnl)1xnggqiz9/b r : w):bv?

  Which statements about the electrolysis of molten aanw ot7-sky2:luminium oxide are correct?
I. Aluminium ions gain electrons at the cathode
II. Oxide ions lose electrons at the cathode
III. The cathode is the site of reduction in this cell

  Which row, indicated in the table below, containop(znumdol, /5vl52 bs the correct species that are produced at each electrode du2/ obupzmdn l,v5(lo5ring the electrolysis of molten zinc chloride?

  Which solution does not produce oxygen at the anode when electrolyzed withpq /p u;v;qo5 oz)i 83fkim1ux inert electrp;3o/fuuxmqi o1p85q )v k ;ziodes?

  Oxygen and water areuz2 ;ostj:*jx64 8ga nlcm tn- produced when nitric acid reacts with potassium manganate(VI*6sa4tct-jg2nz ;j xounm: 8lI),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
1.Define reduction in terms of electron transfer.
2.State the oxidation state of manganese in $KMnO_4$ and in $Mn(NO_3)_2$.In $KMnO_4$:X= ----待选择----+-   , In $Mn(NO_3)_2$:X= ----待选择----+-   
3.Identify which species has been oxidized in this reaction and specify the change in oxidation state it has undergone.

  Which statements are correct about an electrolytic cell?02l 1z 9w+cvqyssk; dl
I. An external power supply is used to drive a non-spontaneous process
II.Oxidation occurs at the positive electrode in the cell
III.The cell could be used to extract a reactive metal from its molten salt

  The diagram below shows a voltaic cell. The overall reaction taking plk-; bz--s y5wcufrlg 4ace in the4flsyg-b ruz-kcw- 5; cell is:
$Mg(s) + Pb^{2+}(aq) \rightarrow Pb(s) + Mg^{2+}(aq)$


Which statement is correct for the magnesium half cell?

  What is the balanced chemical equatixhhk5tf **y52f/tgho on and $E^{\theta}$ cell for the spontaneous reaction between the following half-cells?
$Pb^{2+}(aq) + 2e^- \rightarrow Pb(s)$ -0.13V
$Cu^{2+}(aq) + 2e^- \rightarrow Cu(s)$ +0.34V

  Which statement about electroplating aned 6 itfy.o(.yc,by: g object with silver is incorrect?

  What happens to the x:jgkd(t97 cnewe)u- $Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is l2eg xge z)a 3wkg+l61heated under reflux with an aqueous solution of the oxidizing ag2+k1 w3xga gee)lz6 lgent $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below and the smm,h qv-n6k ob0 5cgi2tandard electrode potentials, determine the standard cell potential of the hvbm-o5qg i m2n6c,k0cell,$E^{\Theta}$.
$Pb(s) | Pb^{2+}(aq) || Ag^+(aq) | Ag(s)$
$Ag^+(aq) + e^- \rightarrow Ag(s)$ +0.80V
$Pb^{2+}(aq) 2e^- \rightarrow Pb(s)$ -0.13V

  Using the following half reactions, how manr1kae()ww a/zjwx 20ghf,-w wy moles of electrons are transferred in the equation for the oxidation of ethanol in the presence of acidified potassium dichromate when balanced/(kr )w gwaww, ejwf21a hxz-0 with whole numbers?
$Cr_2O_7^{2-}(aq) + 14H^+(aq) +6e^- \rightarrow 2Cr^{3+}(aq) + 7H_2O(I)$
$CH_3CH_2OH(aq) + H_2O(I) \rightarrow CH_3COOH(aq) + 4H^+(aq) + 4e^-$

  Electrolysis of $Cu^{2+}$ using a current of 1A for 10s produces x mol of Cu metal.
If Q= It, how many moles of Cu metal is produced if $Cu^+$ is electrolyzed under the same conditions?

1.Draw an electrolytic ceego3;7dmc- 56fjcjl ell for the electrolysis of molten sodium chloride. Label the direction of electron flow and the pola -dl;7j53 jcocfe6m gerity of the electrodes.
2. 1.Deduce the major products if dilute aqueous sodium chloride was electrolysed instead.
2.Deduce the major products if concentrated aqueous sodium chloride was electrolysed instead.

  Which of the below reactions shows the oxidation of a secoea m qz5)eu;3wndary alcohol?

  The diagram below shy.zbawsb2ede+y :u ..ows a Daniel cell. Zinc is more reactive than copper. When the cell is operating, which statement about the ioa.eez u 2.sdw.byy:b+ns in the cell is correct?

  What is the reducing agent in this r58kcmaa*qm isw,3g i;eaction?
$Zn_{(s)} + 2NO_{3(aq)}^-$ + 4H^+_{(aq)} \rightarrow Zn^{2+}_{(aq)} + 2NO_{2(g)} + 2H_2O_{(I)}$

  The below diagram shows an electrolytic cell. At0dtj/y* p-err2b:hl e which electrode will bromine form, and what is the process taking pla-ryperjt*0 b/2: eldhce there?

  The diagram below shows a Danielhp 43fyxpct :; cell. Zinc is more reactive than copper. When the spontaneous reaction occuyx h;p 4p:c3tfrs, which statement about the Daniel cell is correct?

  The equation for the ovk5 )mt2+ -e ndg.jjzwlerall reaction in a voltaic cell is:
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$
Which statements are correct for this cell?
I. Electrons flow from the copper electrode to the silver electrode
II. Silver ions are reduced in the reaction
III. The copper anode will become smaller in size as the reaction proceeds

  What are the respective oxidation states o+ yua3xh,sit/ f sulfur in the following sulfur-containing speci+i3ua t /x,yhses?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with water to form metal h+ilc t 8373s1y 6uprx1fkwkqwydroxide and hydrogen gas.
1.Write a balanced equation between sodium and water.
2.Explain why this reaction is considered as a redox reaction.
3.3 other alkali metals W, X and Y also react with water.
Based on the following observations, arrange the metals in order, starting from the weakest oxidizing agent. Explain your answer. ----待选择----XYW $\lt$ ----待选择----XYW $\lt$ ----待选择----XYW $\lt$

Meta	Observations
W	Slow reaction with water
X	Vigorous reaction with water
Y	Fast reaction with water

  What happens to nitrogen when nitrate changes t;nqqm w; pl;51hbkkg+ o nitrite ?

Sodium metal may be obtained commercially from the electrolysis og8ajhb 3l u(ln5* ij f4.lme6gf molten sodium chloride in a Downs cell. This cell operates as an electrolytic ce3leb4( lg 8* luhamng.jj 6fi5ll.
1.Describe, using a diagram, the essential components of this electrolytic cell.
2.Suggest why molten sodium metal may be collected from the top of this type of cell.
3.Describe two ways in which current is conducted in an electrolytic cell.

  A battery is added to a container 0 r.bst u-fek5of molten $CaBr_{2(l)}$ to create an electrolytic cell, as shown in the diagram below.



1. 1Use section 24 (Section 19- 2025 Syllabus) of your data booklet to identify and write the oxidation and reduction half-reactions.
2.Label the anode and cathode on the diagram above.
3.On the diagram above, label the electrode where calcium metal $(Ca_{(s)})$will appear.
2.A different electrochemical cell is shown below. One half-cell contains a lead metal electrode immersed in 1.0 M $Pb(NO3)_2$ solution. A standard electrode potential table is also shown for elements X, Y, and Z.

Elements	Electrode potential
$X^{2+}_{(aq)} + 2e^- \rightarrow X_{(s)}$	$E^{\Theta}$=-1.18V
$Y^+_{(aq)} + 1e^- \rightarrow Y_{(s)}$	$E^{\Theta}$=-0.45V
$Z^{2+}_{(aq)} + 2e^- \rightarrow Z_{(s)}$	$E^{\Theta}$=+0.34V

1.Label the left half-cell of the diagram with the metal that will produce the highest cell potential.
2.Draw an arrow on the diagram indicating the direction of the flow of electrons.
3.Consult section 24 (Section 19- 2025 Syllabus) in your data booklet to calculate the standard cell potential for the diagrammed cell.  V
4.Use metals X, Y, and Z combined with aqueous chloride solutions of metals X, Y, and Z, and write a balanced equation for a reaction that will proceed spontaneously.

  Consider the following redoxqr6 ejhupm,s2w.7 u 6l reaction:
$Cr_2O_7^{2-}(aq) + 14H^+(aq) + 6Ag(s) \rightarrow 2Cr^{3+}(aq) + 7H_2O(l) + 6Ag^+(aq)$
1. 1.Using section 24 (Section 19- 2025 Syllabus) of the data booklet, calculate the standard cell potential.  V
2.Predict, with a reason, whether this reaction is spontaneous or not.
2.Using sections 1 and 2 of the data booklet, calculate the standard Gibbs free energy change in $kJ\,mol^{-1}$.
The standard entropy change for this reaction is $508J\,K^{-1}\,mol^{-1}$
3.Using section 1 of the data booklet, calculate the standard enthalpy change for this reaction in $kJ\,mol^{-1}$.
$\Delta G^{\Theta}$=  $kJ\,mol^{-1}$, $\Delta H^{\Theta}$=  $kJ\,mol^{-1}$

  The Daniell Cell is a galvanic cell with a standard cell potential of 1.10V.yj mze;)2- kmo
$Cu^{2+}(aq) + Zn(s) \rightarrow Cu(s) + Zn^{2+}(aq)$
1. 1.Define standard electrode potential.
2.List the features of a standard hydrogen electrode (SHE).
Suppose the SHE is replaced by a MMSE reference electrode with a standard electrode potential of 0.64V.
2. 1.Using section 24 (Section 19- 2025 Syllabus) of the data booklet, calculate the new electrode potentials.Cu(s):  V, Zn(s):  V
2.Using your answers to (b)(i), calculate the new cell potential and comment on this value.$E_{cell}$=  V

For each reaction described below, specify its type and write its comple gv p28/v/yovcte balanced chemical equation using the structural formulas of ry/ cpo /gvv82veactants and products.
1.Formation of butane from but-2-ene.
2.Formation of but-2-one from butan-2-ol.

  Titration technique can ( ejgid9y/ h4zbe used to determine the percentage of copper present in a sample of copper (I) oxide. The sample is first dissolved j y eiz/dh9(4gin acidic solution and $Cu^+$ ions are formed. The resulting solution is then titrated against a standard solution of potassium manganate (VII),$KMnO_{4}$. In acidic solution,$MnO^-_4$ reacts with $Cu^+$ to form $Mn^{2+}$ and $Cu^{2+}$ ions.

Titre	1	2	3
Initial burette reading/$cm^3$	2.00	24.70	5.00
Final burette reading/$cm^3$	25.80	48.30	30.60

Mass of copper oxide (I) sample/g 0.7751
Concentration of $KMnO_{4}$ solution/$mol\,dm^{-3}$ $2.375\times10^{-2}$
1.Using Section 24 (Section 19- 2025 Syllabus)of the Data Booklet, write the equation of the redox reaction.
2.Define reducing agent and specify the reducing agent in the reaction.
3.Calculate the number of moles of $MnO^-_4$ that reacted with $Cu^+$.  $cm^3$
4.Deduce the percentage by mass of Cu present in the sample.  %
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.

  Consider the following reactions involving metals and their aqueous nitrh8.eubc7 xn1 6b ;(jrnenbok5ate solu; ku8 r6(b7b.e1nboe 5njxnchtions:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
Metal X		No reaction	No reaction
Metal Y	Grey solid of metal X observed		No reaction
Metal Z	Grey solid of metal X observed	Pink solid of metal Y observed

Choose the correct order of the metals from the strongest oxidizing agent to the weakest?

  Consider the following reackg w zyd20a2,71djwggtions:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below shows the reaction betw oht5/noj8l/ teen concentrated sulfuric acid and potassiu5h8o/tlj n t/om iodide.
$8KI(s) + 5H_2SO_4(aq) \rightarrow 4K_2SO_4(aq) + 4l2(g) + H_2S(g) + 4H_2O(l)$
1.State the oxidation state of sulfur in $H_2SO_4$ and $4H_2S$.In $H_2SO_4$, x= ----待选择----+-   , in $4H_2S$, x= ----待选择----+-   
2.Write the half equations for the oxidation and reduction reactions.
3.Define oxidizing agent in terms of electrons.
4.Identify the oxidizing agent in the equation.

  Consider the following e 5hdloo *2kf6fquations:
Equation 1:
$2ClO_3^-(aq) + I_2(aq) \rightarrow Cl_2(aq) + 2IO_3^-(aq)$
Equation 2:
$ Cl_2(aq) + 2NaOH(aq) \rightarrow NaCl(aq) + NaClO(aq) + H_2O(l)$
Which statements about these reactions is/are not correct?
I.Iodine is reduced in equation 1
II.Chlorine is reduced only in equation 1
III.Chlorine is oxidized and reduced in equation 2