Which of the following statements a xurt6e9tckd-gl2 20tt m.-e5enzw; s z))xtire correct?
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 s:cx* no.neo 1.:cx4 gpxs q8g;h hpyg/mlzg*;tandard conditions for standard cell potentials? . /pgmoq4ogy* e cg; hxl*18sn;xchn:p:z. gx
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is corrllb/kq g51 )dfect?

  Which row of the table is correct for a spontaneo+s dywa)53-qr qngy(aus reaction?

  Which statement about electrochemical /ki7+bipl)n.6bh nezcells is not correct?

  What are the correct products of the re/ xo+z( / k9mjk;qnerwaction of nitric acid and magnesium metalx /wq9ekk+j mznor /(;?

  Which statements abou: znv*oui)9;j fc sw)nt the electrolysis of molten aluminium 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, contains the7+uk dgsqp 4f. correct species that are produced at each electrode during the electrolysis of molten zinc chlo4 ukqsgp+.f7dride?

  Which solution does not produce oxygen at z484biac zmnwzsmf*/-piv8c -(m0i xthe anode when electrolyzed with inert electrode/xzc8ab mp*4ni0vz4 fim( iw-- smzc8s?

  Oxygen and water are produced when nitric acid reacts with61ut a* hvmx7q potassium manganate(V1m7*v qtxuh6aII),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 are8ocio rr+a f,;4 zoyg+ correct about an electrolytic cell?
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 vol+ity ,4z tvh sq)38m;:wbirastaic cell. The overall reaction taking place in the cell 4,iq3i8wb :zv;rsa t+)hsym t 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 equatandug6s/v 6r, jh6a:y ion 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 eleclomo, .-:xrsdv- s vs0troplating an object with silver is incorrect?

  What happens to the ;s./hw2qh,b.(d ehqjy6 vclg $Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under reflux with anwf8d,o p n t(vy4bz9g- aqueous solution of the oxidizing age9f ,(npzwygdt-o4vb8 nt $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below and the standard eley(xp50stf4ei ctrode potentials, determine the standard cell potential5ye4t(p six0f of the cell,$E^{\Theta}$.
$Pb(s) | Pb^{2+}(aq) || Ag^+(aq) | Ag(s)$
$Ag^+(aq) + e^- \rightarrow Ag(s)$ +0.80V
$Pb^{2+}(aq) 2e^- \rightarrow Pb(s)$ -0.13V

  Using the following halk0z3q r ogv44wf reactions, how many moles of electrons are transferred in the equation for the oxidation of ethanol in the presence of acidified potassium dichromate when balanced with whole nuok034z4 r wqgvmbers?
$Cr_2O_7^{2-}(aq) + 14H^+(aq) +6e^- \rightarrow 2Cr^{3+}(aq) + 7H_2O(I)$
$CH_3CH_2OH(aq) + H_2O(I) \rightarrow CH_3COOH(aq) + 4H^+(aq) + 4e^-$

  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 cell for the electrolys gwk4 4)dssr rri3oi; 1q:q;ndis of molten sodium chloride. Label 4:skrq;dr1)r soni;3 i4 qwdgthe direction of electron flow and the polarity 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 reaction8am ,;chtgnqypx 2f s81u02rw s shows the oxidation of a secondary alcohol?

  The diagram below shows a Daniel cell. Zinc is more reactive than copper. Whfrg0.a qih46r9 d2k2k(cvjgp en the cell is operating, which statement about the ions in the g. ipr jv(2af6qk2c9 4kg r0dhcell is correct?

  What is the reducing agent 4c v h/p9h2uqkin this reaction?
$Zn_{(s)} + 2NO_{3(aq)}^-$ + 4H^+_{(aq)} \rightarrow Zn^{2+}_{(aq)} + 2NO_{2(g)} + 2H_2O_{(I)}$

  The below diagram shows an electrolytic cell. At which electrode will 4gt)ccmpy sr0 u a:/,cbromine form, and what is m caccpg:0ysr, t/4u )the process taking place there?

  The diagram below shows a Daniel cell. Zinc is morg1p7cavqdv-g5.tp.-v) xnhbtb0 t/ r e reactive than copper. When the spontaneous reaction ca db0vtb. 5 v)ghn-/v7r. tgx-pt q1poccurs, which statement about the Daniel cell is correct?

  The equation for the overall r0tcmg*p,q*afmt 3qob 3lw 1(weaction 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 of sulfur in the fx+qiccub/e f 5l 2 yb)v(.hx(eollowing sulfur-containin/5+ul ybc()x(qv .efcexh bi 2g species?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with water to form metal hydroxide and hydroqf2jmd) +:jbnqcbx1 (gen 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 1 +)zchua6fbfx27yklnitrate changes to nitrite ?

Sodium metal may be obtained commercially from the e * svp 1sul/ ,evm7.bc8. hrv;bxsf0dylectrolysis of molten sodium chloride in a Downs cell. This cell operates as an electrolytic *u sse 0.8 x.,h;sbcv/yl 7prfm1dvbvcell.
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 iw b-5;i -bbwncontainer of 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 redoxkk*0h20i dgso 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 standa q2ic wo0lcl d4kc2we.h9.wo0rd cell potential of 1.10V.
$Cu^{2+}(aq) + Zn(s) \rightarrow Cu(s) + Zn^{2+}(aq)$
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 comp:3 ll3io7,mzxwyi h .dlete balanced chemical equation using the structural formulas of reactants and productl,. oh3 :mxyl i3i7wzds.
1.Formation of butane from but-2-ene.
2.Formation of but-2-one from butan-2-ol.

  Titration technique can be used to dete,h4d,mz,imyg bly q(3rmine the percentage of copper present in a sample of cop,zdg, bmhmy qliy (43,per (I) oxide. The sample is first dissolved in 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 m g0 tyj +j.:0 m5*vwnirysvaj;etals and their aqueous nitrate solu ram0is tj;+g.ny5v*:0wvyjj tions:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
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 reactions: dcbgc jebe ,+dt0ph,8+)b wv5
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below shows the reaction betwee n6.( yo6xnhi *a(zzgqn concentrated sulfuric acid and potassiua. xgn* 6((q6nyozz ihm 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 equatioh1rulfwh2.ibg20 d v/ ns:
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