Which of the following o i7zvzya/xeb6 49s8 wstatements are 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 standard conditions for sta80bq)fzle2 r andard cell potentials?qae0lfr8b )z2
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is cornuq57hvou keq/ vmzi.)ck :, 4rect?

  Which row of the table is correc- e h7eepb.hwnaq e0+7t for a spontaneous reaction?

  Which statement about e 4 :b2 l +l) yp/ux-oc/fxtecyydekb4,lectrochemical cells is not correct?

  What are the correct products of the reaction of nitric acid and magnesiumdru : mkjavane5(g./2 metal?mg/jdk:va 2 an5(.rue

  Which statements about the electrolysis of molten hf 5h ,e64koi pk4lml-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 the correct species that z ;- urdc)ba2eare produced at each electrode u) -c azder;2bduring the electrolysis of molten zinc chloride?

  Which solution does not produce oxygen at the anode when electrolyzed with inert-t*kwiz+ k d78n3 pglj electrkd8-+ *7ln 3wpzigkjt odes?

  Oxygen and water are produced when nitric acid reactj f.zg2te8lwcld72, us *g8se s with potassium manganate(Ve22 gu.ls8edj*g,tcwfl8 7z sII),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 l6+ 75vzuza0vrk*huh 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 voltaic cell. The overall reaction taking place in19b/ m0xv6kcs:3 fwlsz* m jrz the cx/k*ms9 m3:1czzvjfwbl60srell 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 eqzh/k/ jv1ljg k*7 js6quation 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 an object with silver is incorrez *kw2po3iniq6tc ( rros3w0*ct?

  What happens to the 0mlg d6*o j7u) )+e 4h fxh1yyszezsh1$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under reflux with an aqueous i:dzrp 8,j)pq )ecydag6/c* 1t sk+kksolution of the oxidizing age: ycjp1zdadt kcks))/+ k *r8pi,6gqe nt $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below and the stand3t8c / cs m9bh g;sp4qkmebfzbe/2,h4ard electrode potentials, determine the stanbp,b3z e ct/ bshe49/8 ;mc2 shmg4fkqdard cell potential 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 half reactions, how many moles of electrons are tr59+r n9( uclf7bpi,si-qdo fs+h l 2ouansferred in the equation for the oxidation of ethanol in the presence of acidified potassium dic (ln f-ciporou52d9qu7f+sbls + ,ih 9hromate when balanced 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 cell for the electrolysis of molten ssek w8m18pxyu3e/)e fodium chloride. Label the direction of elec)us8 wmpke /x3e1y8fe tron 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 reaction:ygy5-fy (gi4u:dr s ys shows the oxidation of a secondary alcohol?

  The diagram below shows a Daniel cell. Zinc is more reactive lcezzds r4rn79xe/el47n1p2 than copper. When the cell is operating, whic9l7p e1rxn7/eznz2 rlc4 de4sh statement about the ions in the cell is correct?

  What is the reducing agentj) u d(i/d,eiyy-/wro in 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 cellgw.nw/ 6q b bj7xi)y;e. At which electrode will bromine form, and what is the process taking pjgnwxb)i7;w e 6.yb/ qlace there?

  The diagram below shows a Daniel cell. Zinc is more reactive th z4y2(z0je;7l6a hlvialu pa/an copper. When the spontaneous reaction occurs, which stateme6zlal7i h yaz /0 upv(42;jlaent about the Daniel cell is correct?

  The equation for the ove *kmn cgm/a 0zf1ue67vrall 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 of sulfur in the following-cp:9- r f*epjz2kb cx sulfur-containing specie* j:x2r9bkfe -c-zp cps?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with water to form metal u y5ktyyfof (8piufn 4y/px*z 379yq0 hydroxide 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 nitra af; pn(7+*bi8 t/al/*n ylmrbd-ljgzte changes to nitrite ?

Sodium metal may be obtained commerci -qy zr0ct4(7qc z-etq:2pkxcally from the electrolysis of molten sodium chloride in a Downs celzq0ec(rt4pcq-2c kq-xzt7: yl. This cell operates as an electrolytic cell.
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 x( d5 yn8qr*w9y9nfb ya container 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 ur d nb)g8k )e79dv lncme;9+sredox 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 5f6e:ar9 kh, 7ucu13gsv7o zda3 ywv xwith a standard 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 writ1x h9bhg*gf dj ;+e;nye its complete balanced chemical equah;fghengdy+ xbj19 *;tion using the structural formulas of reactants and products.
1.Formation of butane from but-2-ene.
2.Formation of but-2-one from butan-2-ol.

  Titration technique can be used to determinz06v5x2/s z umr4y sofe the percentage of copper present in a sample of copper (I) oxide. The sample is first dissolved ins/rz5x0uof6m sz y24v 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 2d;. m,io)9 abj/ nc h)avbde (mpes*wreactions involving metals and their aqueous nitrate solutiondoj*.p; ,hb2/ ()s9i a)e nvcbewam dms:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
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 reacti00ispdb:knp mpx4,)c.ma(k tons:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below shows8a5j(ytpp5 ec the reaction between concentrated sulfuric acid and potassium iodide5e5pj(t yp8 ca.
$8KI(s) + 5H_2SO_4(aq) \rightarrow 4K_2SO_4(aq) + 4l2(g) + H_2S(g) + 4H_2O(l)$
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 equatiouyt )kl7n3 w lnxr:l2-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