Which of the following statements are c5et.nj9ia n9+zobab: orrect?
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 con kp+e9js+ +:m ae(grp5g tfd/o)ue )pvditions for standard cell potentials? +)e jkpp )ro dev+(asguge+m:tp5f/ 9
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is correc am4m*cqd .cfkr/.(sx t?

  Which row of the table is correct41/tle -qar rp7k 7wkc c)*pvf for a spontaneous reaction?

  Which statement about electrochemical cells * (t9 l6 rdcg(uuyqyj+is not correct?

  What are the correct products ofo9 1-a odc.epj the reaction of nitric acid and magnesium metal- 1j.o 9adpcoe?

  Which statements about 9mrfk/41x ixq ae l)n25kek(othe 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 thy a.afmn 2r+-ke correct species that are produced at erk.y2a-mf a +nach electrode during the electrolysis of molten zinc chloride?

  Which solution does not produce oxygen at the anode wht7fn dzuld8 +4en electrolyzed with inert electrode nd+u8t7d l4fzs?

  Oxygen and water are produced when nitric acid reacts w1ja6 mhrt9;pwps8yo8 ith potassium manganate(VIIa1mp86owt r9hp 8jy ;s),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 cp)wolxh ky.7f z7:lz 7d 0+tctorrect 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 j4cnfd9 t vb6-ruy;4)ohn siti64o9 p a voltaic cell. The overall reaction taking place in the cell is:utt9y4ps rn9 nfi6 4;bj-hvcdo )4i6o
$Mg(s) + Pb^{2+}(aq) \rightarrow Pb(s) + Mg^{2+}(aq)$


Which statement is correct for the magnesium half cell?

  What is the balanced chemical equagw(bj2dgac /tg )ne)*-dqj n.tion 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 abou1gdu 5ljb ,fe qi1g)x:jwy2 9jt electroplating an object with silver is incorrect?

  What happens to the 2 cy+thlmp*d-vc7tuy 5* o6 vr$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under refluu) xwgv/kne iq v-nv:3f.,hw(x with an aqueous solution of the oxidizing avv xguk3q) ,/h-wwv. n(nei:fgent $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below and theezf(oluh86ld )8v3x 6crgfp;y6bu e5 standard electrode potentials, determinuo6u6fd plv ee3 8zcy)l(;6g b 85fxrhe 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 reactyp)u c8lx)s1hions, how many moles of electrons are transferred in the equation for the oxidation of ethanol in the presence of acidified potassium dichromate when balanced wit)8x1 cuyp) lshh 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 chlomp mq nf-8qh27ride. Label the direction of electron flow and the polarifm7q8hnp-qm 2 ty 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 ox,:qg kr: dmg(u*qv t9xidation of a secondary alcohol?

  The diagram below shows a Daniel cell. Zinc is more reactive than cra)qpr u :7cx/2 m5atdopper. When the cell is operating, which statement about the ions in th r2)m pa x/rcqa5d7u:te cell is correct?

  What is the reducing agent (p4l 14;gikwuq fnph,atp9*st,d8ud 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. At which electrode will bromineyj 9p5 0w5krjn form, and what is the procjp5 nwy950jk ress taking place there?

  The diagram below shows a Daniel cell. Zinc is more reactive than copper. Whefoe kf,*sqh*bq9(j. cpj-f )z,w u l, aql(gp-n the spontaneous reaction occurs, which statement about the Daniel cell is corr(cff pz,s*a pbqfq-9l*joe j h,k w(qgl,. u)-ect?

  The equation for the overall reaction in a voltaikx+ood5 - kp:vd pah9:c 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 oxidjcd jh/oy5ogrq5m 6pp79d qge+0i2+d ation states of sulfur in the following sulfur-containing species? /dq p r5+moj2ed+6dghjy7 pci 90q o5g
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with water to form metal hydroxide and hydrogen gash-pmzhk0r c 0x8z3i: r.
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 nitrogesml2vlafob l2 3 y5jvxm-7+.tn when nitrate changes to nitrite ?

Sodium metal may be obtained commercially from the elecfpr1uiz 5 l5a2v:y6pk;5fezwtrolysis of molten sodium chloride in a Downs cell. This5yuvrw2 zf5a1;zkp: 5 f plie6 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 aorjz t3k/t439 d7e8ahd .y q djg2sci1 container 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 reactio,2/ w qqzm6 ;y)mfegvrn:
$Cr_2O_7^{2-}(aq) + 14H^+(aq) + 6Ag(s) \rightarrow 2Cr^{3+}(aq) + 7H_2O(l) + 6Ag^+(aq)$
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 of 1.10V.l/;8z 50qi3/n iolt g8pltvp n
$Cu^{2+}(aq) + Zn(s) \rightarrow Cu(s) + Zn^{2+}(aq)$
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, *ze tjsx6peu fq--7r3specify its type and write its complete balanced q- tz7r6-ux* fjpees3chemical 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 cc nx 1fq13z;goan be used to determine the percentage of copper present in a sample of copper (I) oxide. The sample is first dissolved in acidic sz1; c3qofxng1 olution 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 involvingz6io,vw:.h* ymu6; dcbj -s tg metals and their aqueous nitrate soluc t,:vo;i6 g-zsbu*6 hymjw d.tions:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
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 reaac) vl m gz9; bdnq+uj(x(q*i2ctions:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below shows the reaction between concentrated sulfuric acidjbq04q: o8g npocen+8 and potassiun+pejnq8g 0qco 84o:bm 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 eq,8x/ agcrs t(wuations:
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