Which of the following statements are corf 0sdxsmmf n4 fh7hl9ac0,/x2ai,s r. 9g5tugrect?
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 forpl 3)80 b-xk d9 tjsdnj57kyin standard cell potentials?8 dx0sntp7jin3)dk 9bjy 5k-l
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is cor8kh dfc/c0xl .(jjktys5 9rs6i0 f 9vnrect?

  Which row of the table is e (0zawek,n,b correct for a spontaneous reaction?

  Which statement about electrochemical cells is not corr8ru6p x;eu:l/q8 wvfmgp p o24ect?

  What are the correct pr6 g8 *d(sfvddcoducts of the reaction of nitric acid and magnesium metal?d68 *vdcfd( sg

  Which statements about the electrolysis of molten aluminium oxide are c99q c) 9dj ylqpxs (5sfa8ygd/orrect?
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 tul7z- ;,ru82 az hbaepable below, contains the correct species that are producezp- ezb u7a 2;8,ulahrd at each electrode during the electrolysis of molten zinc chloride?

  Which solution does not produce oxygen h4/ 0ju3o-j* +uo m3jdytkzasat the anode when electrolyzed with inert el*3uj kzs 3 yt aomj-j40uodh+/ectrodes?

  Oxygen and water are produced when nitric acid reacts with potassium manganate(V8t don nig /w2b a j6fmc+q7r)1fj9g9sII mrn igt j/7+b 126a9ds nofgf9c)8qwj),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 electrol7,uy-(comg p 42 egjtoytic 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. 5f7*qxz d i0ojfydzu8ed 7-o overall reaction taking place in the cell iszoef-uo jf. *5 dz dq77i0xy8d:
$Mg(s) + Pb^{2+}(aq) \rightarrow Pb(s) + Mg^{2+}(aq)$


Which statement is correct for the magnesium half cell?

  What is the balanced chemical equb t .gp(bnwd4, rzgr 14rzy/f8ation 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 sil-q 76kkd8ymveb :xnh /ver is incorrect?

  What happens to the sx.aph.u,. y nug8q 2y$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under reflux with an aqueous solution jjk;-7c :a t)sdvzl3gof the oxidizing agen-;ak37l dcsg jv)t:j zt $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation u0.3hhe tcbm8k 4cl:1)r gmdagiven below and the standard electrode potentials, determine the dc)h 30eh:mrt8g lucm a4.kb1standard 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 transferraov i*14tb-kt90 mv dqed in the equatio0vta- it*qdkv1bo49m n for the oxidation 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 celo2mes e 6j75vke4j 9zll for the electrolysis of molten sodium chloride. Label the direction oej7m25oj6vk sz e l9e4f 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 rejz:px zj5)r6 eactions shows the oxidation of a secondary alcohol?

  The diagram below shows a Dan k0/2;o m3ez.3 lv ajlaxdvba/iel cell. Zinc is more reactive than copper. When the cell is operating, whi3 bdl vm/.aaxzve k/;j3al 0o2ch statement about the ions in the cell is correct?

  What is the reducing agent in this reacytkpo7:- /uz2:7a q9utngjh* 9tcvhxtion?
$Zn_{(s)} + 2NO_{3(aq)}^-$ + 4H^+_{(aq)} \rightarrow Zn^{2+}_{(aq)} + 2NO_{2(g)} + 2H_2O_{(I)}$

  The below diagram shows an electrolytic cell. At which electrode will bru*j/533y roa j:udqly:l51lpwiskmpm gz.1 8omine form, and what is the process taking place thla5/5l8r l*:3sjy1zy3quk.1:m umiowppjdg ere?

  The diagram below shows a Daniel cell. Zinc is moc/dto9bc /u) (r6xuf v7a ro(mre reactive than copper. When the spontaneous reaction o u9a/buo6xmftr/)7(d cocvr (ccurs, which statement about the Daniel cell is correct?

  The equation for the overall reac+pjpoeu vm9zo: s759s*ghvt)tion 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 statlj3/-wn/ kgpc aq4v t,kfk.go)+-rmbes of sulfur in the following sulfur-containing specg .fk/ 3vpnoq )wl-c+k/rgmk,4b -jaties?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with water to form metal hydroxide and hydrogen gas. n7)aa/zwq auk:; opf5
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 change pj.6yue * zd-qajv/s9s to nitrite ?

Sodium metal may be obtained commercially from the elecj 5b(ezhe v6 zv *o*izrzvy(w+cb5+ /mtrolysis of molten sodium chloride in a Downs cell. This cell operates as an (/zbevz vh5w6zm +(rji5 *ovc*+by ezelectrolytic 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 coiq9dkav e/kljli-( qj;g-e/ / ntainer 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 7uw ir laf:x;iu-z +h;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 galvani1 3oa1pc6nz3h gyacr,c 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 below, specifcjfthej*3l /1:4 djw.2ayc4zhxs m 6w y its type and write its complete balanced chemical equation using the structural formulas of reactants anc.3*e/1 2t jx4cy fs hl4 6djajzmw:whd 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 mgf4v85ps su )9stg,sof copper present in a sample of copper (I) oxide. The sample is first dissolved in acidic solution and 9 4svspmg8)u5,sst fg$Cu^+$ 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 mn peyix 82j0qugg.x23etals and their aqueous nitrate solug pg2yjxxni8ue 320 .qtions:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
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 followinw,k22m5gsek4xcxvyt+-jp p5g 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 shows the reaction betwee u -(vh2e hufi3wqc25nua.hb/n concentrated sulfuric acid and potassium iodidc -av.w 523 f2h/neuuu(hqhibe.
$8KI(s) + 5H_2SO_4(aq) \rightarrow 4K_2SO_4(aq) + 4l2(g) + H_2S(g) + 4H_2O(l)$
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 q:eydv,m/by7 rvko :1equations:
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