Which of the followingrt3u wh;6cna)y cn+ci)m rrfo)0 38t/wsy 4w c statements 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 sku(a .,i(4 dj-zkolzq. j0f owtandard conditions for standard cell potentials?j.i4kdlw.fj(u -o0k( oqaz ,z
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is cor :b xk)6glv0ap 0kt2lb7)z gofrect?

  Which row of the table is correct for wj*7 g* nf;u gmayi(v5h*g uf2a spontaneous reaction?

  Which statement about electrochemical cells ik sj-u;e2a :;qnedh w/s not correct?

  What are the correct products of the reac c,4synqfpkg ;:tk(v0 tion of nitric acid and magnesium metal? 4 n;0ykf:pkc( ,vgtsq

  Which statements about the electrolysis of molten aluminium oxide arj) b*lbxw-8 hc2 7wgige 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 tablxloc7j-je* k0 1krx0 ue below, contains the correct species that are produced at each electrode during the1x-k 7uolrexjk c*j00 electrolysis of molten zinc chloride?

  Which solution does not produce oxygen at the anode when electrolyzed with inertyh m:wtd)t4zibf)3r vd0.fllzfd 1;u-rl ( ;c evlt(0t)ff;dru;4l 1irmf dc yl b zdhz 3:)-w.lectrodes?

  Oxygen and water are produced when nitric acid reacts with potassium manganate(Vm;ody* m*s:fr Idsf ro*my ;:m*I),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 u5 r( 6gwt/ zpw7-uxs6fk7 r:i7uh gvaan 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 volta:hl; -)aapdxn-vfz-wiz3sh. ic cell. The overall reaction taking place in the cell hhd pl3 -z.x:ai-)f;w-v sz anis:
$Mg(s) + Pb^{2+}(aq) \rightarrow Pb(s) + Mg^{2+}(aq)$


Which statement is correct for the magnesium half cell?

  What is the balanced chemical equation az(j,ttlu:7fwha0 y ukr: o(a(nd $E^{\theta}$ 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 me8ote7,ud n/with silver is incorrect?

  What happens to the dqq)mi,aiu x9.mi1i. $Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is hevoqd n1ap ,zb)qsc8d2(/ lf7tated under reflux with an aqueous solution of the oxidizing /ds vntobl q p7z(8a2fdc) q,1agent $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below and thiu6+cn fm241 yxxahg,/gu)m qe standard electrode potentials, determine the standard cell pou4a1f+c 2u /)mqxmxnhyg6ig, 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 electrons are transferredtyr.d8x3l s7g in the equation for the oxidation of ethanol in the presence of acidified potassium dichromate whelsdrt.y738 xgn 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 tljj z8u4ipdf a4 jxjn2(q (y:3he electrolysis of molten sodium chloride. Label the direction of electron flow and the polarity of the n j2(f( z:ijjqdl8auy44pxj 3 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 thnggg*h d2)( wze oxidation of a secondary alcohol?

  The diagram below shows a Daniel cell. Zinc is more reactive than coy (y fm je)j0z -y2 a//iakj2q(n;nloopper. When the cell is operating, which statemenm(jj2 zkooq ay)0y ni-a2lj(/;/feynt about the ions in the cell is correct?

  What is the reducing agent in wg 4o-i3ihr dz+:gf 4;+lwwps 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 willeequzfb;o) h 8( t/bx 5kda4w7 bromine form, and what is the pro )ued q8 / tek7bhza(5of4xb;wcess taking place there?

  The diagram below shows a Daniel cell. Zinc is more reactiveflq5w(o brj w( lc;5c+suv-s8 fi)pk5 than copper. When the spo8brk)cp55q-f (ilvl5 cu;w( f jw +ssontaneous reaction occurs, which statement about the Daniel cell is correct?

  The equation for the overall reaction in a voltaicxbf lfun;fmjy1 ysw3 (;a 00(iv+j*a a 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 oxidatior r-tf 4;s,luw .2(sqksr0idjb /ht3 qn states of sulfur in the following sulfur-containingq rs-qi ku;0f.j/ l 4d2,3wtr(t hssbr species?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with wate-hk;5u s0ubr8t:u- p thjnaw 9r 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 wsm;j:;x; b i z3a+j;bzdg -4;jaubspshen nitrate changes to nitrite ?

Sodium metal may be obtained commerc2*xl,yd88 afgp9w8fnon ra e5ially from the electrolysis of molten sodium chloride in a Downs cell. This ref 8,poxd* y fw95a8n n2g8lacell 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 ff(p-s f2/1 vc56 o)pc 2 wwoh kfna4sf1c-ttmof 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 redsbt3mzr n 2.v-ox 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 nppufaqzhb/ :jw 8yq7-a*-)q with 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, speq y;)kke 8n5rwcify its type and write its complete balanced chemical equation using the structural formulas of reactants a8nk)er5 kw;yq nd 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 determine the percentage of copper p; 0zhu+i9ww 9cwr 714cd osntpresent in a sample of copper (I) oxide. The sample isdzw497 wcr+u ni;cp10 t9shw o 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 metals and their ;9 tr;)ws mtt1o sn)r odkq/wu: pr:h+aqueous nitrate soluti +/s:mkn;dt:1 t r)o) rw;tshq9wruop ons:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
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 reactionsq:- kv2q2y,w pu .mqgt:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below shows the reaction between concentrated sulfuric acid and 8i sz s:+.z;8i (rwb yltju9fepotass9tiz8s.wu(j:y;bs+ if rezl8 ium 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 equatiovf7esv9z3b 8m +g*mlcns:
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