Which of the following statements are correct? )w 5 dwqv o wj0di8uta)v3sf5cq )j;:o
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 standard cell potential/84ifk xhliai,y5d 7w s?i8waf 5iiy74 / lkxh,d
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is cwc+s8an42(rdaz lca.q 21gk y orrect?

  Which row of the table is correct for a sponywp1it3.0 xe *,g(b wav65 proq(pjpgtaneous reaction?

  Which statement about ela+;ju:v6 /v of ropu.w7ux, byectrochemical cells is not correct?

  What are the correct products of the rea8jnea/l sald +.)wz u0ction of nitric acid and magnesium metal8j0lsd./eunaa ) w z+l?

  Which statements about the electrolysis of molten aluminium oxide cp0i;6x4osa c8 q 9lxvwd fac +ss9.075 ppvlhare 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 spedo2f /ow3o v0ecies that are produced at each electro wo0ov2doef/3de during the electrolysis of molten zinc chloride?

  Which solution does not y12wr+mgu vtxtircnwf 5 /)c qr83d/2 produce oxygen at the anode when electrolyzed with inert ew3rwt qc2rgc)8 xm/ du+y irt15/nv2flectrodes?

  Oxygen and water are produced when nitric acidt :d 4ui5ooy oc(qa3uy je.9 .i;q6ns( ky3qpt reacts with potassium manganate(VI:yp(c6jq (93 qn o. ; ds53.oyioet uukiyaq4tI),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 corremtozsy/ (n) 0mct 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 voltav76 kc ga3bp/iy14aohaz jq4 0ic cell. The overall reaction taking place in the 6z 3ijoc4vhkaa4yp 01a7q gb/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 equation an, 5rc47gt ;j hy9qgupbd $E^{\theta}$ 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 witqzpout8n vm54d o c/ 48v i1y7yyje(;ph silver is incorrect?

  What happens to the mi vx))xlvdn 3)) 4tcdu3v2k3ualk2b$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated und,n4 bcbnp5or2 er reflux with an aqueous solution of the oxidizing agent p2nrbbc o, 5n4$KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below an8aq p:eicdb 3soa q/(7d the standard electrode potentials, determine the standard cell po:d3os/ (e8cqqiap 7ba tential 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 j:)6z ,oq q.zye.e nadelectrons are transferred in the equation for the oxi yq., noa6:).ed zeqzjdation of ethanol in the presence of acidified potassium dichromate 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 electrolysisolspg .03b2 ul of molten sodium chloride. Label the diru 23s0olbg. plection 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 reactions shows the oxidation of a:(8zgqc5ecn(q 8b bvx secondary alcohol?

  The diagram below shows a .x; gppl: hy4jlr:ak/r ef+y,yilcv0 (s9 u1eDaniel cell. Zinc is more reactive than copper. When the cell is operating, which statement about the ions in the cell9k: lypl4el (u0x;rrh1e+yga.,vpj/f iscy: is correct?

  What is the reducing agent in this reac(cz(xbw27+ nq4sdlz ytion?
$Zn_{(s)} + 2NO_{3(aq)}^-$ + 4H^+_{(aq)} \rightarrow Zn^{2+}_{(aq)} + 2NO_{2(g)} + 2H_2O_{(I)}$

  The below diagram shows an electrolytic cell. At wlu++( wk*w/;.iuoeqbx7k/3tg r ;r uk kumx+khich electrode will bromine form, * + wq uxw(3/rx k; uigreuktk+ /mkubl7k;+o.and what is the process taking place there?

  The diagram below shows a Daniel c:m6kfr.j sz.n9ks279fc ubs pell. Zinc is more reactive than copper. When the spontaneous reaction occurs, which state.k 7bjr k9:cssz6mnu9sfp .2fment about the Daniel cell is correct?

  The equation for the overall reaction 87sg2rf/xqo l/wcz2. rz5okt 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 followi2t qx 6b/b.tbhng sulfur-containing speciesbhb2.bx/qt t 6?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with y:uqe w0;1 p6g 6qxolowater to form metal 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 nitratea -+:rla h2+r bk)zm( kobh9ay changes to nitrite ?

Sodium metal may be obtained commercially from the electrolysis of moltenr,:v gu5 ecw ;70hntju sodium chlow5c, ;gvnjur:et0u7 hride in a Downs cell. 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 a container of molten v s9 99nvv2kie$CaBr_{2(l)}$ 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 redox +61m8 m3 jcuzn)rxdrjreaction:
$Cr_2O_7^{2-}(aq) + 14H^+(aq) + 6Ag(s) \rightarrow 2Cr^{3+}(aq) + 7H_2O(l) + 6Ag^+(aq)$
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 ce7 2 yiyppm sogxc)0dr: hz07.nll 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 /lk6zx i7m, f onm/ht-below, specify its type and write its complete balanced chemical equation using the structural formulas of reactants and produc-zt i6xhknolmm ,f/ /7ts.
1.Formation of butane from but-2-ene.
2.Formation of but-2-one from butan-2-ol.

  Titration technique can be used to determine the percentage of copper pres+xld0/egt hp( 5;bo8gejhz.czf8 wm4 *g 7cf pent in a sample of copper (I) oxide. The sample is first b.+ 7l(mgo*f ;wzg5ee 808c4 thfxdp/pzgj hcdissolved 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 metals and theip:( bohuf2bj1w 8kwzz4 pk-o6r aqueous nitrate solutions(bw o-kb pf8 h24zju1z:p6okw:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
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 reactitn;t(sb pj m f.:y3l;qons:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below shows the r;:bd+tt-+. spd: m(dat9nvdt7 vojomt;w :sqeaction between concentrated sulfuric acid and potassium iodi9at dvtwnp- +m;sms;qdv + t.dotj:t 7::b(dode.
$8KI(s) + 5H_2SO_4(aq) \rightarrow 4K_2SO_4(aq) + 4l2(g) + H_2S(g) + 4H_2O(l)$
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 eqyju/a t dj*61pqwi:s1 dq0hg*uations:
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