Which of the following statements are cc105pfp.xf l 0l, musnorrect?
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 sta u vs64z/ pkobrq/3o5bndard conditions for standard cell potentials? vkuo prb o5bqs/3/46z
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is correctyqy4(/ :cb ,bt7uw6. uim glnb?

  Which row of the tab 3lm-)gu.ziqxle is correct for a spontaneous reaction?

  Which statement about electrochemical cellsar8 + c9xlk+jxwo . s3cif0u*w is not correct?

  What are the correct products of the bsm0s; i/;hu6bv u)xu reaction of nitric acid and magnesium metalm/vxbs)ubu0 6su;i;h ?

  Which statements about the electrolysis ofs.k1p)s jn-vg 2 rhzx4 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 arpn x1-rrh0hn 0e produced at each electron1 r0-n hxph0rde during the electrolysis of molten zinc chloride?

  Which solution does not produce oxygen at the anode when electrolyzed with inecdv(0 s -yog)ert electro()go de0c svy-des?

  Oxygen and water are produced when nitric acid ree a, mga 1i)uxp0qy:oz-,9,.nmwyk laacts with potassium manganate(Va ly 9pmgu,oy,)k-ziw ne.,:m1a qx0aII),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 electrolytic ce+jc(l v/tt,q11 ftg dwll?
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 reaction taking placql0c67 eoj:u pe in the cell0p7ecj o uq:6l 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 )0-uejuo+d ph,j q oy4equation 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 a p/do/sv*(a hnn object with silver is incorrect?

  What happens to the xjge)/ /vj5:)o0k qrj0/vf bk cdlap;$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under reflux with an aqueous solq2,nfm 0)5otz j;ei 3lkyi lh+ution of the oxidizing ,;mqi32nzliehyo t) fklj5 +0 agent $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below and the standard ej ikc0fms 2h 81(f.j*giabp8vlectrode potentialj vhc.28*f1sk f bjap8i0m( gis, 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 electrons an4yst-v95 twy- kjf x2re transferred in the equation for tjfk24 vy s 5y-t-xn9wthe 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 cell for the electrolysis of molten sodium chlori)g6w 3wm3 pwuide. Label the directipwwmw36 )uig3on 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 shv s3c eafb) (t3uk.tc 8k/-3t3isuppxows the oxidation of a secondary alcohol?

  The diagram below shows a Daniel cell. Zinc a y4,v2rbky8tfjf0j) 2 otrr6 is more reactive than copper. When the286 fbt2tfr)rr04kajoy,j yv cell is operating, which statement about the ions in the cell is correct?

  What is the reducing agen/8 (c pqi pts*rw(f0tht in 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. A ixj a55mw+c2s*yq ,i ryhz*r(t which electrode will bromine form, and what is the proces yj2(cyia,+i5 r *w5mxsrhz*qs taking place there?

  The diagram below shows a Daniel cell. Zin4ojzd 3;2byzzc is more reactive than copper. When the spontaneous reaction occurs, which statement abo o4z3;jz2zbdy ut the Daniel cell is correct?

  The equation for the overall reaction in a voltaic cells4xy/sj hk) m. 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 fo-jp+ w1(qvq)xjjg bu-llowing sulfur-containing specbv-g j )+quwxj pq-(j1ies?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react wb o,,x+hdql53 xw8yw u2xrz;x ith water 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 when nitrate fche2+jc gq; ,j ja.(achanges to nitrite ?

Sodium metal may be obtained commercially from the electrolysis of molten s/phk smho) g hqhlk8a9 -/80x3(-bg lbbxue (podium 8/ph(bah/ 0- lmq9)-xlkpoxuhs 3kggh( b8eb chloride in a Downs cell. This cell 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 of7.o1 fmhpw:i eza6/kf 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 followizgcs*gg9 7 xqpk 3qo+ws /+.ybng 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 galvfs93br1 ud 4pnanic 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, specify its type and write its comple1)h /qlue vn f h(74izd,qd:yjte balanced chemical equation using the struc7 1dq/eiqh4yj)fz h ,nluvd :(tural 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 determine v7m9fya7)eb:r zf a 3qthe percentage of copper present in a samplee):ybfa a9rqv77z3 fm of copper (I) oxide. The sample 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 aqueous nitratjin. 22mvc nq 2xl.:mte soluti.m:cmlv jn ix2q.22nt 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 followind*rajg 6*l4 jbg 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 between concentrated sulfuric acid7tx94c hvjq +q and potassium iodide cj9+4qxv 7thq.
$8KI(s) + 5H_2SO_4(aq) \rightarrow 4K_2SO_4(aq) + 4l2(g) + H_2S(g) + 4H_2O(l)$
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 equatioe7* rm1p8cgsfns:
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