Which of the following statements adp- s 1v gc9)lyousw/;re 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 po ,m/clr:z/*zlswb ,m rtentials?*cz/m ,ml bwr/:lr ,zs
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is co4hr/-sh s+dn7 u2hb :9bw(rbtw;offqrrect?

  Which row of the table is correct for a spof /xcy(mza(p3 5cvg6bntaneous reaction?

  Which statement about 1+*59l tsnvc nm pm +v c(.nyu*wx6zcgelectrochemical cells is not correct?

  What are the correct products of the reaction of nitric acid ant-)l;k.aguy2azjtf(xyo6 f qe:.tx / d magnesium metal fjyxlqk6ft(2 uxayz;t. ta:g./e)-o?

  Which statements abou;+ e;tqvfqvog) ,5cbr t the 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 thr1c 9r-c4n/u 9 spdhj9kqtk,ae correct species that are produced at each electrode during the electrolysis of molten zinc chloridc-/cpr4qk1k99 9tju nrahs d,e?

  Which solution does not produce oxygen at the anode when electrolyzed c4zd1.ek 0jjdk s.zb( with inert electro j14k zdk(zcesd 0..bjdes?

  Oxygen and water are producsrj20fk)mxg 1 ed when nitric acid reacts with potassium manganate(Vx jkrfms 2)10gII),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 abo*x:cqb : ye;oiut 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 overall ri4u tzu+p/xq0 *t v/vjw9bm4i3s c f31dw*jwoeaction taking place in theqidu 1cvxuzj itjws3w/ t494b/*+mp03v*w fo 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 af8 zpi *vq*,7x (a,wcfa pnic8haa.( 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 silver is incorr7a1g n)4ym+qv/ h b yv+ nctas;pi4o-nect?

  What happens to the dc yu2g c:7tu)$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under rs4 jf 9s8c+wocp fe1y.eflux with an aqueous solution of the oxidizing agj4s9 yfpw .o+1cc8f esent $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below and the standard electrode p w hu f6cof-xww (zge g7 82;)ptb)ojyr7u20tkotentials, determine the standard cell potential of the cellx ;8p-g)7jkb)7 tg0u cww2fohtour2wy z( f6e,$E^{\Theta}$.
$Pb(s) | Pb^{2+}(aq) || Ag^+(aq) | Ag(s)$
$Ag^+(aq) + e^- \rightarrow Ag(s)$ +0.80V
$Pb^{2+}(aq) 2e^- \rightarrow Pb(s)$ -0.13V

  Using the following half reac1y 96xftgaf s8tions, how many moles of electrons are transferred in the equation for the oxidation of ethanol in the presence of acidified pf yxf8tg619asotassium 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 electrolysis of molten sodfkrrqjw0,+qk 9/z;g 0q*zsri ium chloride. Label the direction of electron flow and the polaritqk/qq +g9*z 0 kr,wfjz; 0irsry 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 xy69d a4he4p f el7yfs4b:x(rsecondary alcohol?

  The diagram below shows a Daniel cell. Zinc is more rdq/ilwc10 , 5wrvw28 b0 ywlbyeactive than copper. When the /vd,b1w0cwb0l rliw2wyqy 85 cell is operating, which statement about the ions in the cell is correct?

  What is the reducing agent in t bl+417ybil slw2 wa/ghis 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 wil85ff k )y5zzc)8lgq tvl bromine form, and y85zz) g)8f5 qctfkvl what is the process taking place there?

  The diagram below shows a Daniel cell. Zinc is more rea )cj-d wa*vk448gr cpictive than copper. When the spontaneous reactio )*k 4d -gwv4icjarc8pn occurs, which statement about the Daniel cell is correct?

  The equation for the overall re ;1nii o*mtvyfhb:6+daction 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 qq l)-q j*jo3q2n4fth the following sulfur-containin-4qjj2hft )*3q lqqong species?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with water to form metal hydrox3eba c*xrux.n rt:9h f6 s4cu,ide 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 wha f.daseur5v5 t-g x1z: y4wy;en nitrate changes to nitrite ?

Sodium metal may be obtained commercially from the electrolysis v40 d7*a7- gk; b-vdsuupbvzz of molten sodium chloride in a Downs cell. This cell operates as an electrolytic ces0 ;ud -gbb7vzda4pku* v-zv7ll.
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 moltel-i z/wg0nht+1uh nwzf6acex * at70)n $CaBr_{2(l)}$ 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 reactidf,6g/v*s) fg hsuy4 ion:
$Cr_2O_7^{2-}(aq) + 14H^+(aq) + 6Ag(s) \rightarrow 2Cr^{3+}(aq) + 7H_2O(l) + 6Ag^+(aq)$
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 selv qpr.c)vs,9bh7bx6 u37ow tandard 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, specify ithh(b;. /uai ;dcu3ksjqxd5te( a n 3(hs type and write its complete balanced (eau33x; i(d nt dbhq5ah(uk.s;/ch jchemical equation using the structural formulas 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 deter rdoppm.,e;zwt94 u-wmine the percentage of copper present in a sample of copper (I) oxide. The sample is first dissolveddz-.; orm9e w,p 4pwut 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 involvieovr- qaj;17sxqm+q4 hu2v 2l ng metals and their aqueous nitrate solutionvrjo -2+qa14v;hqu lx2 me7sqs:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
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 reacyyxc1p9l(y6 n tions:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below shows the reaction between concentrated sulfuric acid and pok /szo52 *ck hxn3lc53nhgtai-7yd 4otassium iodido3c2a4 n/ogki c*l-k 75shz y5nxd3hte.
$8KI(s) + 5H_2SO_4(aq) \rightarrow 4K_2SO_4(aq) + 4l2(g) + H_2S(g) + 4H_2O(l)$
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 equations:*m7hhp 36: taeezvo4v
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