Which of the following statementu9izv)+l 4zb hk3sj1sv p*zj9s 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 standard cell pote ,t1qdovm fi(:ntials?1itoq ,:d vmf(
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is corre)dcm*r0hh 0 30k lvofxct?

  Which row of the table is correct for a spontaneous reaction ,wy .0korgn9a?

  Which statement about ele,5qwiv5 e5d rfw4s 5qtctrochemical cells is not correct?

  What are the correct products of the reaction of nitric acid and magnjjw315a 3b* 8 -suo -stkuxbooesium metalo83351aj- xsw k*ojb ubos -tu?

  Which statements about thez1m:l.ct i,me 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 the correct species that l ; x e:3,xyu lf(gqu.wrx7tc.ujl*m:ikhp4 6are produced at each3wuc (x6*eh tg7ixl.:p, 4ulfyjqm . :lruk x; electrode during the electrolysis of molten zinc chloride?

  Which solution does not pro06;dl a vlqi3wduce oxygen at the anode when electrolyzed with inert elecd3iw lqa;vl 60trodes?

  Oxygen and water are produced when nitric acid reacts w)lel (ry*h wt+zub;nzuq ar6:-) gyt 3ith potassium manganate(VIIer l *z (t)nzrtyah3y +6uuqw)l- g:b;),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 *7nsqj:,bqgn7jedw2s qst0 - 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 overallx58op,+ su)9s ln 5bpesg:gik reaction taking place in the cell ss),9n osbikp elg5pgu:5+x8 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 chemvam 7q+-lojetr/p/f /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 abouz*3) b3jftrekt /ci7 nt electroplating an object with silver is incorrect?

  What happens to the 89qk disvko)l-y+1f z$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under reflux wi x(4b:zuzy;e ;ybs el*th an aqueous solution of the oxidizing aey eyz4b;*x(:sbzu;l gent $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below and theq t-fdnk81 yjflx-w+xa, l-t1 standard electrode potentials,- 11w,-j y-lkxntqxtlaf 8 df+ determine 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 moles of electrogc/,. yzz,gpgi g8 ielz52 h5vns are transferred in the equation for the oxidation of ethanol in the presence of acidified potassium dichromze, ipy28g gv izgl5,5/zhgc.ate 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 el(0 e0g+n d-rsbc-rdw lectrolysis of molten sodium chloride. Label the directionslgr bn0( -wrc0ed+- d 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 oxidatioh8. gh6t-ns 3r v0-czlnav)/te sdkd6 n of a secondary alcohol?

  The diagram below shows a Dani *e3wc q+lr7vfius.*o el cell. Zinc is more reactive than copper. When the cell is operating, which statement about the ions in the s+r37oi u*qcv lw*.efcell is correct?

  What is the reducing agent in thts6vz (itq; i9xd:cq7is reaction?
$Zn_{(s)} + 2NO_{3(aq)}^-$ + 4H^+_{(aq)} \rightarrow Zn^{2+}_{(aq)} + 2NO_{2(g)} + 2H_2O_{(I)}$

  The below diagram shx/ iz 8;,4zpo7alts cpt21utcl tty- 8ows an electrolytic cell. At which electrode will bromine form, and what is the process taking place t4 ,zzcttp7;t 2c88 sxyotip/ -1 ltaulhere?

  The diagram below shows a Daniel cell. Zinc is more rmqdd*z*u fa2*yef qs/ny.2k: eactive than copper. When the spontanem szdanf*uy2*k ye. q*d:f/q2 ous reaction occurs, which statement about the Daniel cell is correct?

  The equation for the overall reaction in+,h oi 2jjqepwzs6+ ixf:q)afdd 9u,; 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 follow95w)al,iou6c -pfet+6 wgn hsing sulfur-contai9hwe+ sc-f5gu tl6)a np,6owining species?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with water to foc rtsb3a+07fq;j7o 8 c9qedkurm 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 nitrate changes to nitrite x90bnya-mgdu* qs d*7 ?

Sodium metal may be obtained commercially from the electrolysis of molten sodiumla*aesqv*hrw+* o u( j*m f/2f-lclx6 chloride in a Downs cell. This cell operates as*m2/h6sqlao a rcv fle * *-*jx(luw+f 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 molll:z 2,atubc j.i. w+yten $CaBr_{2(l)}$ 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 followiambf03:(ok 6yv ,sl4 if/*u )rcx +dtku;izfwng redox 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 galvanicbxwj76bz rov2 *;g;y b*f3zs u cell 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 bemv( )kdy 08gd6 zckcqy 9trv),low, specify its type and write its complete balanced chemical equation using the structural formc gdd ,ky6(z80tqc my)v r9k)vulas 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 ;a ,kw :uk.;:wcxkhmaf( wrf6 determine the percentage of copper present in a sample of copper (I) oxide. The sample is first dissolved in acidic solfh:wma:uw akk ;(6xw rfc.,k;ution 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 the2n9(ct 5vwwxxs8 h0+infyo a; ir aqueous nitrate solutio (8 fya9tsvn0 wiw25nx xoh;c+ns:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
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 reacte pg)tdro)7a i1zd. z2ions:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below shows the reaction between conwe c2lgvje 0de-:qzfep,* 29yk 6,uspcentrated sulfuric acid and potassium p j0-ud 6,9e* wlgepqe22ky,sce zf:viodide.
$8KI(s) + 5H_2SO_4(aq) \rightarrow 4K_2SO_4(aq) + 4l2(g) + H_2S(g) + 4H_2O(l)$
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 eqem 9(wzhp7sk::i. -loh kthy +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