Which of the following statements are9b. ,o 0yzzz*msa 9:- gkvckqp 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 t(1bn-idmayu(8h2e,so osh4g 3gmdo0 he standard conditions for standard cell potentials? ao2edio u48 - bygs h,dms3h0(n(m g1o
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is correct?j6ri i . h5sh oiom n)tb,*gweiv37,*l

  Which row of the table islv-c/ m-vds5 w correct for a spontaneous reaction?

  Which statement about electrolj44w,8df cydnp.y8rh3w2zz /x/egg chemical cells is not correct?

  What are the correct products of the reaction of nitric acid and magnesium bzi t5: p y;6tvidj8y2metal?; it26p yit5b8y:zdjv

  Which statements about the electrolysis of molten alumkxngspolmh;uvdu 4*7uk6, +kl ;c3: m inium 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,a(h pt*3pxg 2c contains the correct species that are produced at each electrode during the electrolysis of32 x apg*cth(p molten zinc chloride?

  Which solution does not produce oxygen at the anode 7)u .0us7fv9ivnb7 w *dl fnjkwhen electrolyzed with inert ej)0udi7f.kufs bv wn 977nl v*lectrodes?

  Oxygen and water are produced when nitric acid reacts with potassium manganate 6(ath+jsxt-i (VII at sijx+-h(6t),$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 eles*:)t oowq(e8cp.htl xz4ak;ipov :,ctrolytic 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 reaction taking place 4 nd5fsqc ;x:md6e i;kin the cell iknd ;s e5;xd46ifcmq:s:
$Mg(s) + Pb^{2+}(aq) \rightarrow Pb(s) + Mg^{2+}(aq)$


Which statement is correct for the magnesium half cell?

  What is the balanced chemical equation awu5hfi5 9z o7j9pea )rnd $E^{\theta}$ 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 aboutnginr a i:56tk12 +s ibr*2zmg electroplating an object with silver is incorrect?

  What happens to the 9p(1xb dk 9( otnho8um$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under reflux with an aqueous solution of the oxid n,p:u4qk zy:(:htsmdizing agentq:,:ds(mht :n k4zu py $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notation given below and the standard electrode pom q8ii5 /abi. ;sjc+aotentials, detea bcm+./ii5;q8i sojarmine 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 are transfxo kopzjc -m k rc-.0k4vs7(9gerred in the equation for the oxidation of ethaoo kkk z9( r4msx-0jpg7 v.-ccnol 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 cheoyimy;tdx:nj- +un 2/)p i(yloride. Label the y; (yndn-yjp +)oxit m/2 i:eudirection 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 shows the oxidation of atff 0fu 57r fb)zb,emp6iingj55 q/ 7t secondary alcohol?

  The diagram below shows a b8/h)(x9 5c vaxll iioDaniel cell. Zinc is more reactive than copper. When the cell is operating,b) v( ola8c/5hixx9li which statement about the ions in the cell is correct?

  What is the reducing agmmhj0v w/10tj4c c l+2u mcy*lent 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 wiutl4 whos+bbb *,,r3c ll bromine form, and what is the process taking place th,w *lbu,bhbt r+s 4oc3ere?

  The diagram below shows a Dani kywuva0c*69uel cell. Zinc is more reactive than copper. When the spontaneous reaction occurs, which statemenvwc96yua0*u kt about the Daniel cell is correct?

  The equation for the overal/vca:z d3kmp: l reaction 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 : 4ox ek;8.;uh p 8lvqz2ohqtathe following sulfur-containing spu.;2ehoav:p qt4 ;ok 8lq8x hzecies?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with water to form metal hydroxide and hydrogen lej9*p v j6: s.awuzb4gas.
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 changes to nitrib xbe/:2n8j r3b1)oybasj*ia te ?

Sodium metal may be obtained commercially f3e qz:dpp/z2 9 n7kyehrom the electrolysis of molten sodium chloride in a Do/ 3 q z7p29:zekdeynhpwns 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 cos;a0n f9;okv8v- ou 2sogo/sqntainer 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 reactionnvqfeky ful 9+4cmm5();hib .:
$Cr_2O_7^{2-}(aq) + 14H^+(aq) + 6Ag(s) \rightarrow 2Cr^{3+}(aq) + 7H_2O(l) + 6Ag^+(aq)$
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 standarlimj a*7l zx :2y6tx.rd 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 descrii2a;b sz(x5+u:h/l:nu edm pobed below, specify its type and write its complete balanced chemical equation using the structural formulab u/i za2o5:;(:m+lhdnxpes us 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 pm jk 3m1t5s)ube used to determine the percentage of copper present in a sample of coppem kts)p51ujm 3r (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 followingtm8k hh451sxm reactions involving metals and their aqueous nitrate solut8m hthsm4xk5 1ions:

	$XNO_3$	$Y(NO_3)_2$	$Z(NO_3)_2$
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 reactionstd- fh+ ty3zr9:
$Fe(s) + Cu^{2+}(aq) \rightarrow Fe^{2+}(aq) + Cu(s)$
$Fe(s) + 2Ag^+(aq) \rightarrow Fe^{2+}(aq) + 2Ag(s)$
$Zn(s) + Fe^{2+}(aq) \rightarrow Zn^{2+}(aq) + Fe(s)$
$Cu(s) + 2Ag^+(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)$

  The equation below shows the reaction between concentrated sulfu 8sukm *ikk3-y )gql(kee8:huric acid and potassium k q(ukel )i-kyk38m h:g eus8*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 equywzs. vhs2 j,q98rqj,aqn(,eg:6yo aations:
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