Which of the following sty b;fb4oqs2 s7atements 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 4:jhl euklk03 conditions for standard cell potentials?3 k:kjl4le0u h
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is corre .jafkrap2 eo2j*v htp6 5)*uuct?

  Which row of the table is correct for a spontaneobp 8cbzg,ly ,y,9 8fscus reaction?

  Which statement about l10hvc6e i,rk: ntbva1jy,uz 79es3yelectrochemical cells is not correct?

  What are the correct products of the reaction of nitricr h0(a-ugnx.jpg m :)/f rozie5v5:ev acid and magnesium metalr o g5 n:5v age)i/:zum(jep0vx.hr-f?

  Which statements about the electrolysis of molten aluminiuvn .(/3 sc (lpn,xadqmm 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:y4h-et5bb)ms xfnnq kc1 +w3 the table below, contains the correct species that are produced at each electrode during the electrolysis of molt)nbtkb+n1q3-: yc wfs hem4x5 en zinc chloride?

  Which solution does not produce oxygen at the anode when elect sua-mts15od:w 1fy5grolyzed with inert elect5f d1gs tyoam-su :w51rodes?

  Oxygen and water are produced when nitric ace 7ql) jojuy;9id reacts with potassium manganate(VII 9o;j 7)uejylq),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 exs/ 0u/z w9bi:s3vzk mlectrolytic 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. Th28ajkx/pro b( l5qb i yd1ng:(e overall reaction taking place in the2:bondi(q(8jkpy agx/b51rl 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 chemt8hv y3k-.z dmvy8txr ,7om y,aowx+/ical equation 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 silveriu. 63r.jvu. beb fny/ is incorrect?

  What happens to the b qei. u+81kkj gc*mlryu9ps9 lnw4 **gq4id-$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under reflux with an aqueous solu.dvv vplk) 1swjf n (ujt.1rt4+* 4jwution of the oxidizing agent 4v+.1(wvk.tt1l us * )j4dwfjvrjun p$KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell no0u (gu4om b gc.:zm*kltation given below and the standard electrode potentials, determumlk g 0*bmzcgo4:.u(ine the standard 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 :76zl,lk2do:adgz x ) ageuj. moles of electrons are transferred in the equation for the oxi uo6za d :kjl)g2z .g:l7dxea,dation 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 electroxc:m4h 7q6vimlysis of molten sodium chloride. Label the direction of electron flow and t7m i:qcxhvm 64he 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 reacti8wmr 70rhccc pbf l-bv60x6g3 ons shows the oxidation of a secondary alcohol?

  The diagram below shows a Danz 6qpo7psnob x,3i4cd t p+:z,iel cell. Zinc is more reactive than copper. When the cell is operating, which statement about the ions in the cell is correcd,p:qp3 cx7 z4tiszb+ no,op6t?

  What is the reducing agent in this5-:ckzoyfl u23m (dn j+ lg9n0igy g6i 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. Atp3z83 r vbpx7208hkjxa7bj6.auzzo dx g6e q1 which electrode will bromine form, and what is the process tax6ujba0x 8b . pvaz78jke d6 3hz1zxg7p q2r3oking place there?

  The diagram below shows a Daniel cell. Zinc is(r 4w hm-0resx-1j+t oz 1ql72kdi esp more reactive than copper. When the spontaneous reaction occurs, which statement abou+rz4-hqj-s drme2 (exw ik107 olps1tt the Daniel cell is correct?

  The equation for the overall rea0yqk(jr a83eak3*o2uv ec 9 ssction 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 v frgh4l 9xt)+sulfur-containingv9f)4+ r lhxtg species?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with water to form metal hydroxide and hydrotkiid;we* r-5qabeq8g(w + f-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 nitrate changes to nitrite ?4v+:w)i cdmgf1- wkjz sh1;f m

Sodium metal may be obtained commercially from the electrol*g oy hd0a-:mtlty2m2 ysis of molten sodium chloride in a Downs cell. This cell operates as an electrolytic cel2ylm2:hym-dg o0 ta*tl.
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 containes+svdrnnq* jj5+x bi ub664 y(r 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 redox reaction:r*xsioap3ypnu4 8 3x.z4w ,zf
$Cr_2O_7^{2-}(aq) + 14H^+(aq) + 6Ag(s) \rightarrow 2Cr^{3+}(aq) + 7H_2O(l) + 6Ag^+(aq)$
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 edwd,-yf anr6z5) wf 6appc g,e6;-omof 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 writ+zyen*+nxj: *gv0 bdpl k1s//ak kz8ne its complete balanced chemical equation using the structural formulas of reactants and producna*/gnk dkz1ze k0pl8+xnjv/ + y:*sbts.
1.Formation of butane from but-2-ene.
2.Formation of but-2-one from butan-2-ol.

  Titration technique can be used to detertm2hgm( 1yj r k-c-fy2mine the percentage of copper present in a sample of copper (I) oxide. The sa2my ghy-fc1r j(2tk- mmple 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 metals and their aqn kqu,)zax :3vueous nitrate solutiqa:x 3nu)k,zv 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 followi1hjtqkuy f (jrb/y58(ymmmt3 d+45x ong reactions:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below sho6 e tv(bys(q 9blt2v ac 0ykfbi,0ta3-ws the reaction between concentrated sulfuric acid and potassa t(6y 0v2kiafey 9lq,vc3t-bb(b t 0sium 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 equationsbx)il88g dzo/6dd/ fr:
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