Which of the following statements are cor3sfv*:rb d h:l,pvg;ov4m v-m rect?
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 sitvg/ tykq0),tandard conditions for standard cell potentials? qt)ik 0tyvg/,
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is corr 0(mjawj. ffv wxabh53 -j4t:mect?

  Which row of the table is correct for a spontane4x (9b7spj:)wt irkr uous reaction?

  Which statement about electrochemical cells is not correct?rxgvsgj1; pq1e(1 /vh 0d sn(2 ,zef)zktina(

  What are the correct products of the reacti f8++ wnxmkli(on of nitric acid and magnesium metal?k(+ xfiw8 +nml

  Which statements about the electrolysis of molten aluminium oxide are corplb0j9g e(38a*+zshac cy+vbrect?
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(xbn qcwqj:6ag67) t p in the table below, contains the correct species that are produced at each electrode during the electrolysis of molten qa6wjgb7:q xp (6)cnt zinc chloride?

  Which solution does not produce oxygen at the anode when electrold-y/ irpwr9; dyzed with inert electri9-py rdwdr/; odes?

  Oxygen and water are produced when nitric afuj1 fkkx,3 5ztd+jz6cid reacts with potassium manganate(V zt 1fz+x jj,3kdu5f6kII),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 electrolyt74.mwomhf 48,jl rvxyic 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*9ox9s74p ty2 n2dke5ikwj fj voltaic cell. The overall reaction taking place in thejdknofwx9t ke*yp2ji2 5479s 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 cbh gj a,g*am;hv 4huf 5(gh0o8hemical 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 electr+pc-n / fd2cyuoplating an object with silver is incorrect?

  What happens to the akq(cdoi/n-if - 33h8,azf zq$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under reflux with an aqueous solution of the onxj;ydg.*t8 uxidizing agd u;gjx.*t 8nyent $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below and the st9gg9o 6l5 s:eg(bjc xsandard electrode potentials, determine the standard cell potential of the cell,jgxb5 scoe ls 69(:9gg$E^{\Theta}$.
$Pb(s) | Pb^{2+}(aq) || Ag^+(aq) | Ag(s)$
$Ag^+(aq) + e^- \rightarrow Ag(s)$ +0.80V
$Pb^{2+}(aq) 2e^- \rightarrow Pb(s)$ -0.13V

  Using the following half reactions, how many moles of electrons are try 1 lpx;9ouoyvu3 c1dc 8m(w-eansferred in the equation for the oxidation of ethanol in the prc1odmev8ycly; wu (op9u1-3xesence 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 chlor 2+d niu8.e w3dj+kgt6 knnjd)ide. Label the direction of electron flow and the polarity of the electrodes. idnt2n )jw8k g n+. u3j6k+ded
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 reactioflwe q:a:t/x /ns shows the oxidation of a secondary alcohol?

  The diagram below shows a Dani(vjv3*eth8 w4s 8j7/otjsnju mp4 c1pel cell. Zinc is more reactive than copper. When the cell is operating, which statement about the ions in the cell is corr svsptute 18cnh8vp74/4(oj j3*jwmj ect?

  What is the reducing agent in goc k+u+v*;m8 2fkjasthis reaction?
$Zn_{(s)} + 2NO_{3(aq)}^-$ + 4H^+_{(aq)} \rightarrow Zn^{2+}_{(aq)} + 2NO_{2(g)} + 2H_2O_{(I)}$

  The below diagram shows an electrolytic ary n2/v.d* ,npy tj*l1lhrm8cell. At which electrode will bromine form, and what is the process taking placerjt2l,y.*r8 a 1/ hvdl pm*nny there?

  The diagram below shows a Daniel cell. Zinc is more reactive tsn52 1(x jqb9i unicx-han copper. When the spontaneous reaction occurs, which stateq-x 1 i5ubin(9nsx 2jcment about the Daniel cell is correct?

  The equation for the overall reaction in a voltaic cell is:6s/vg8hk19m rly mbn +
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$
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 0+xzktk0(c5ec3o n3:df 4 r ,0u kjsxk6sgtxsoxidation states of sulfur in the following sulfur-conta4nuos txr3+exzsj0 kk(5 s6k cx0 cdk30 f:t,gining species?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with water to form metal hydroxide an9iq 3mof*o vz.d 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 changeiov)ek97:wgp yj v9zb v v9dj3z+d5 y:s to nitrite ?

Sodium metal may be obtained commercially from the electrolysis ofy pm4;j jinw44zu:;xf molten sodium chloride in a Downs cell. This cell operates as an elecnz44pj;:;4im f wjx uytrolytic 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 d)-hwh fzw dxen,kah.ku 5995 k;(nhgcontainer 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 reaction:ps- 0rmkmg8t mxbx3 m92cs8+y
$Cr_2O_7^{2-}(aq) + 14H^+(aq) + 6Ag(s) \rightarrow 2Cr^{3+}(aq) + 7H_2O(l) + 6Ag^+(aq)$
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 dxx7f +5m 8sxva galvanic 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 de4t9q+ wi:vtku a,fv e3scribed below, specify its type and write its complete balanced chemict:+9vvk 3fea 4 wqtui,al 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 determine the percentage ofxult - uu6rb7r0+vnx* copper present in a sample of copper (I) oxide. The sample is firsnurrtxb0+7lvx u 6-u* t 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 r,,)ak jydbp :6a.j bmmetals and their aqueous nitrate solution ,yp),kmjbrda:a .6bjs:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
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 reactions9mz7 p;8idl fo 8 qozi.l1lmhu.oy0 )e:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below shows the reaction between concentrated sulfuric acid a5t tvm m2b-0tmnd potassiutm2b t-0mvt 5mm 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 equatio+vm qsg- oc i iuq )tep.l4+))wsa0 mr7tq:es;ns:
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