Which of the following statements are corrjs2y r5k(r ;moect?
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 potentevge*s o9* twsave (3z. u7h.iials?*(9vaz 7.wivgso ues h.e3te*
I.A temperature of 298K
II.A pressure of 100 kPa
III.Solution concentrations of $1\,mol\,dm{-3}$

  Which statement is cocmdgw)rp7-1 u 25ve forrect?

  Which row of the table is correc */lej;5ja/4efu 6e5z joif6+keeqszt for a spontaneous reaction?

  Which statement about e11 d)iug/7qhv8zt hel4yd2 lu.f ypx. lectrochemical cells is not correct?

  What are the correct products of the reaction of nitric acid and magnesium met.kp;/17x / jkrvx p2cf:uwqaj 1iv8 qhm f2z9fal?k/q/zp:7128ix;amv.1 fw ck xfjqu9j2hrv pf

  Which statements aboutk 7yxev,(m1l,ve7 qih 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 the co)3h1iql7l klu5o (qd trrect species that are produced at each electrode duh57(l du3ktl )lqq1 ioring the electrolysis of molten zinc chloride?

  Which solution does not produc1 mr l:tl)*xzde oxygen at the anode when electrolyzed with inert electrodes?*)lt 1z rxlm:d

  Oxygen and water are produced when nitric acid re:rtvv9u/bbp : *tzkz* acts with potassium manganate(VII),*tp: bz/ :k*vtuv9rz b$KMnO_4$.
$4KMnO_4(aq) + 12HNO_3(aq) \rightarrow 6H_2O(I) + 5O_2(g) + 4KNO_3(aq) + 4Mn(NO_3)_2(aq)$
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 correc1iv+* e9he6ddu oe qi dn,4lx6t 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 a voltaic cell. The overab9r,2f bd misr75n3hp ll reaction taking place in the cell 7ip5 mb2, ndb h93srrfis:
$Mg(s) + Pb^{2+}(aq) \rightarrow Pb(s) + Mg^{2+}(aq)$


Which statement is correct for the magnesium half cell?

  What is the balanced cheh9shne50dz3 y d/my1smical 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 electroplattxo;o8k0+ ihais: j *5bq(5i( 0 fbagf- udfduing an object with silver is incorrect?

  What happens to the j*dld u rk0hk+o9 )2gj$Mn^{3+}_{(aq)}$ ion when it is converted to $MnO_{4(aq)}^-$

  A primary alcohol is heated under ref+ ; lh.crmg t99x*0y mw,lfkv76tg kpnlux with an aqueous solution of the oxidizing a,9*ylmkkg6+w l.thtrfv cp;m x 0 9gn7gent $KMnO_4$Which of the following is a possible product of this reaction?

  Using the voltaic cell notat*cfu f,l6 mh7tr c:y/dion given below and the standard electrode potentials, detc,7dc t * f/h6:ufmlyrermine 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 trlwi ,;5jlei5-ab 8 svpansferred in the equation for the oxidation of ethanol in thl bwi 5j -v5eilsa;,8pe 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 celly *fdcr+9us2r for the electrolysis of molten sodium chloride. Label the direction of electron flow and the po fs9r*+dr cu2ylarity 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 oxidatiow*n l mo9(*kspn of a secondary alcohol?

  The diagram below shows a Daniel cell. Zinc is mor ly l2w3v4k4ige reactive than copper. When the cell y4lk gw23il4vis operating, which statement about the ions in the cell is correct?

  What is the reducing agent in this reactionvqkeyz7p339h3v0dx+ qv b *og?
$Zn_{(s)} + 2NO_{3(aq)}^-$ + 4H^+_{(aq)} \rightarrow Zn^{2+}_{(aq)} + 2NO_{2(g)} + 2H_2O_{(I)}$

  The below diagram shows an elect a86mfb /cn(u 6f- awroj)rw0trolytic cell. At which electrode will bromine form, and what is the process taking p m)obaau/r nj0tw6c8 w(frf-6lace there?

  The diagram below sh- wdtk:.yp m+p myup6d6yb 87rows a Daniel cell. Zinc is more reactive than copper. When the spontaneous reaction occurs.y:r d pmd-b6p68 twu 7mp+yky, which statement about the Daniel cell is correct?

  The equation for the overall reaction in a voltaic cellt/kah3rr 3 (d).sox 72ochwen 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 o/ty;3f 4uf,rw 2nob vvf sulfur in the following sulfur-containif2uvr fwntv/3yb, o 4;ng species?
$SO_3^{2-}, H_2SO_4, S_8, S_2O_3^{2-}$

  Alkali metals react with wai )y3z8 cuedzcs3ev55 vu7u8vter 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 change(a7vcplus 57t;2jn xsxl, le 8s to nitrite ?

Sodium metal may be obtained commerciuq t4 (0ri sk3pz.*eswally from the electrolysis of molten sodium chloride in a Downs cell. This cell operates as an electrolytic crsi4kpuz t 30qe( .ws*ell.
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 containeb .f2bhc;wim.m /*quor 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 reac6qy xnovm*/lb4 d 8z:xtion:
$Cr_2O_7^{2-}(aq) + 14H^+(aq) + 6Ag(s) \rightarrow 2Cr^{3+}(aq) + 7H_2O(l) + 6Ag^+(aq)$
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 potezt hw ;.sev98intial 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 belo vfl9asv vg-r0 wr+ky+4bj,cu1jj8 . lw, specify its type and write its complete balanced chemical equation using the structural formulas of reactants and product f-vlr+.9syk 4a08vjw l1rug j+bv cj,s.
1.Formation of butane from but-2-ene.
2.Formation of but-2-one from butan-2-ol.

  Titration technique c rh:lxsgaf5 ,jx5)1 jsan be used to determine the percentage of copper present in a sample of copper (I) oxg5s5xhlfa):jj r s,x1ide. 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 nitrate;+6syqyi w -cv solutiwcy s;i- qv6y+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 followinp1c4 ufvk.q8bg 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 acid an0hjr gp6 11hlvd potassium 01rlhgvj61 hp 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 following3g0i.zh8q i cx equations:
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