2 Br- -----> Br2 + 2 e-Full equation. Label the diagram to show the purification of nickel in the laboratory 50. The oxidizing agent is the dichromate(VI) ion, Cr2O72-, which is reduced to chromium(III) ions, Cr3+. 2) Find how many faradays have passed through the aluminium oxide in 5 hours. The net reaction is the same. Metal ions receive electrons at the negative electrode, and the non . The aqueous form of potassium hydroxide appears as a clear solution. The electrodes are made of metal. The half-cell reaction at the anode in PEM water electrolysis is shown in Equation (4): . Potassium hydroxide, also called lye, is an inorganic compound containing the chemical formula KOH. The half equations are written so that the same number of electrons occur in each equation.. Pb 2+ + 2e- Pb (lead metal at the . Electrolysis is used to separate ionic compounds into their constituent elements. Equation 5: Electrolysis of KCl. . Solid Oxide Electrolyzer. Potassium hydroxide is of low toxicity to marine species. The next step is combining the two balanced half-equations to form the overall equation. These electrodes are separated by . As before, the equations are multiplied such that both have the same number of electrons. Atomic Structure and Bonding, Electrolysis, Acids and Alkalis. This can be tested with a pH indicator such as phenolphthalein pink . Electrochemical cell 2 SCT Page 4 of 26 (d) After acidification, 25.0 cm3 of a solution of hydrogen peroxide reacted exactly with 16.2 cm3 of a 0.0200 mol dm-3 solution of potassium manganate(VII).The overall equation for the reaction is given below. The source of the required electricityincluding its cost and efficiency, as well as emissions resulting from electricity generationmust be considered when evaluating the benefits and economic viability of hydrogen production via electrolysis. The oxygen atoms are balanced by adding seven water molecules to the right: \[ Cr_2O_7^{2-} \rightarrow 2Cr^{3+} + 7H_2O\nonumber \]. AEL and PEM electrolysis operate in the low-temperature range and SOEL in the high-temperature range. Click here to check your answer to Practice Problem 13 Click here to see a solution to Practice Problem 13 This paper presents an experimental study of hydrogen production by alkaline water electrolysis using Zinc alloys as materials for cathode. potassium hydroxide electrolysis half equation. The fully balanced half-reaction is: Cl 2 + 2 e 2 Cl Next the iron half-reaction is considered. When water is alkaline, there are ions in the water to conduct electricity for electrolysis to occur. The ionic equation for the magnesium-aided reduction of hot copper(II) oxide to elemental copper is given below : \[\ce{Cu^{2+} + Mg \rightarrow Cu + Mg^{2+}}\nonumber \]. As a long-standing Head of Science, Stewart brings a wealth of experience to creating Topic Questions and revision materials for Save My Exams. will conduct electricity. The reactions at each electrode are called half
Add to flask with prussian blue small amount of water until it will become a thick slurry. Fe(OH)3 was prepared on the surface of NiCo-MOF by . The LibreTexts libraries arePowered by NICE CXone Expertand are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. Study with Quizlet and memorize flashcards terms like Ionic bond, dot-cross diagram and electronic configuration of a sodium atom, dot-cross diagram and electronic configuration of a sodium ion and more. Causes eye pain, tearing, redness and swelling. The ethanol to ethanoic acid half-equation is considered first: \[ CH_3CH_2OH \rightarrow CH_3COOH\nonumber \]. It is a strong base that is marketed in various forms including pellets, shells and powders. Example: Electrolysis of sodium chloride solution The ions present in the solution are: sodium ions chloride ions hydrogen ions hydroxide ions Na+ Cl- H+ OH- At the cathode The positive ions are attracted to the negative cathode. The aqueous form of potassium hydroxide appears as a clear solution. The hydrogen peroxide reaction is written first according to the information given: \[ \ce{H_2O_2 \rightarrow O_2} \nonumber \]. A half-equation is balanced by adding, or taking away, a number of electrons equal to the total number of charges on the ions in the equation. The overall chemical reaction is, 2 H 2 O (l) 2 H 2 (g) + O 2 (g) 303. nF. Therefore, the first equation is multiplied by 3 and the second by 2, giving 12 electrons in each equation: Simplifying the water molecules and hydrogen ions gives final equation: Working out half-equations for reactions in alkaline solution is decidedly more tricky than the examples above. It is slightly soluble in ether. Save Comment. Hydrogen fuel and electric power generation could be integrated at a wind farm, allowing flexibility to shift production to best match resource availability with system operational needs and market factors. There is a net +7 charge on the left-hand side (1- and 8+), but only a charge of +2 on the right. Credits: Design, Text, and Demonstration Kelly Houston Jetzer University of Wisconsin - Madison, Madison, WI 53706; Video 2NaCl (aq) + 2H 2 O (l) H 2(g) + Cl 2 . (Potassium bromide does not have an equationit has a formula: KBr.) This can be tested with a pH indicator such as phenolphthalein pink. Extraction of Metals. The solution may be represented by K+(aq) and Cl(aq) At the positive electrode (anode) the following happens: ClCl +e. 4. Combining the half-reactions to make the ionic equation for the reaction. 1:59 (Triple only) write ionic half-equations representing the reactions at the electrodes during electrolysis and understand why these reactions are classified as oxidation or reduction .
These hydrogen production pathways result in virtually zero greenhouse gas and criteria pollutant emissions; however, the production cost needs to be decreased significantly to be competitive with more mature carbon-based pathways such as natural gas reforming. The electrolysis of copper(II) sulfate solution. The solution may be represented by K+(aq) and Cl(aq) At the positive electrode (anode) the following happens: ClCl +e. Electrolysis melt of potassium hydroxide to potassium produce, oxygen and water. The reaction takes place as below: 2KCl + 2H 2 O 2KOH + Cl 2 + H 2. 2K + 2H2O -> 2KOH + H2 The hydrogen-releasing reaction makes potassium metal so dangerous around water or moisture. When the cell is attached to an external source of electrical energy, electrolysis occurs. At the negative electrode. 2K (s) + Br (l) 2KBr (s). For example in electrolysis of brine: ANODE: 2Cl- Cl 2 + 2e-"Two moles of chloride ions are oxidised to form one mole of chlorine molecules, and two Faradays of electrons flows from the anode around the circuit to the power supply" CATHODE: 2H . Cl2
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Hydrogen produced via electrolysis can result in zero greenhouse gas emissions, depending on the source of the electricity used. KOH is an example of a strong base which means that it dissociates completely in an aqueous solution into its ions. This alkali metal hydroxide is a very powerful base. Potassium reacts with bromine at room temperature to form potassium bromide, Write a chemical equation for this reaction Include state symbols, Potassium bromide exists as an ionic lattice, Potassium bromide does not conduct electricity when solid but does conduct electricity when molten, (ionic): made of, positive and negative ions / anions and cations / oppositely charged ions / unlike charged ions / different charged ions, (lattice): regular / sequence / pattern / alternating / repeated / framework / ordered / organised / network / uniform, Explain why potassium bromide does not conduct electricity when solid but does conduct electricity when molten, Concentrated aqueous potassium bromide is an electrolyte, substance that conducts electricity / (undergoes) electrolysis, molten or liquid or solution or aqueous AND containing ions/or ionic. An electrolysis of an aqueous solution of potassium chloride is carried out by employing a fluorinated cation exchange membrane having an ion-exchange capacity of 0.8 to 2.0 meq/g dry polymer and having carboxylic acid groups as functional groups and maintaining a concentration of an aqueous solution of potassium hydroxide in a cathode compartment in a range of 20 to 45 wt. Alkaline water electrolysis is a key technology for large-scale hydrogen production powered by renewable energy. Combining the half-reactions to make the ionic equation for the reaction The two half-equations are: H 2 O 2 + 2e - 2OH - Cr (OH) 63- + 2OH - CrO 42- + 4H 2 O + 3e - If you multiply one equation by 3 and the other by 2, that transfers a total of 6 electrons. Potassium Hydroxide | KOH or HKO | CID 14797 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities . 806 8067 22 Registered Office: Imperial House, 2nd Floor, 40-42 Queens Road, Brighton, East Sussex, BN1 3XB, Taking a break or withdrawing from your course, Official Chemistry 2023 Applicants Thread, A100 Medicine for International Students 2023 Entry, Official Dental Hygiene and Therapy (Oral Health Science) 2023 Entry Thread, A-level Combination for Cambridge Economics, Biomedical Science: 2023/24 Applicants Thread. the same number of electrons
The evolution of oxygen gas bubbles in potassium hydroxide solution is observed in situ under microgravity by a charge-coupled device camera, focusing on the wettability of a platinum electrode . Legal. It is represented by the . This reaction happens in preference to the reduction of potassium partially because reduction of potassium ions would produce potassium metal, which would immediately react with the water, oxidising again to potassium hydroxide and hydrogen gas. Test Your Knowledge On Potassium Hydroxide! Best uni for MSc in Marketing - Bath, Warwick, Durham, Birmingham, Bristol, Exeter? In this video we will describe the equation KOH + H2O and write what happens when KOH is dissolved in water.When KOH is dissolved in H2O (water) it will diss. Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. Potassium hydroxide is also known as caustic potash, lye, and potash lye. The balanced half-equation and the type of reaction occurring at the negative electrode is: . The liquor is. GCSE Chemistry
(a) The electrolysis of copper(II) sulfate solution. Solid oxide electrolyzers, which use a solid ceramic material as the electrolyte that selectively conducts negatively charged oxygen ions (O2-) at elevated temperatures, generate hydrogen in a slightly different way. electrolysis cell) In electrolysis we use half-equations to show what happens at each electrode. To reduce the number of positive charges on the right-hand side, an electron is added to that side: \[ \ce{Fe^{2+} \rightarrow Fe^{3+} } + e-\nonumber \]. Meeting the Hydrogen Shot clean hydrogen cost target of $1/kg H. Reducing the capital cost of the electrolyzer unit and the balance of the system. Your Mobile number and Email id will not be published. UCL postgraduate applicants thread 2023/2024, Health and social care unit 6: Work Experience in Health and Social Care, Some Tips for Students That Increase Learning Power, Official Oxford 2023 Postgraduate Applicants Thread, Official: Keele University A100 2023 entry. . The rules for balancing redox equations involve adding H +, H 2 O, and OH - to one side or the other of the half-equations. This can be verified by adding a pH indicator to the water: Water near the cathode is basic while water near the anode is acidic. Designed by leslie kritzer legally blonde role | Powered by, condos for sale knolls drive, stony brook, ny, Issuing Authority For Driver's License Texas, Allianz Index Advantage Variable Annuity Surrender Schedule, professor nickel has four labs and a lecture class. The Formula of Potassium Hydroxide. Here, bromide and potassium ions are present at their lowest or highest oxidation state, respectively. Iron(II) ions are oxidized to iron(III) ions as shown: \[ \ce{Fe^{2+} \rightarrow Fe^{3+}}\nonumber \]. (HT) Be able to write half equations for the reactions occurring at the electrodes during electrolysis, and complete and balance supplied half equations. State and explain what happens to the concentration of zinc sulphate (2mks) (d) State the ratio of the products of the anode and cathode using the equations (2mks) (f) Give one use of electrolysis (1mk) (g) What is anodization of aluminium (1mk) 4. Anode Reaction: 2H. 2 lbs of Potassium Hydroxide (KOH) per container shipped in an HDPE container with a resealable child proof cap. - Concentrated aqueous sodium chloride, using inert electrodes. See some other examples of
This page titled Writing Equations for Redox Reactions is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Jim Clark. It is used in various chemical, industrial and construction applications. Write an ionic halfequation showing what happens to the chlorine molecules, Cl 2, in this reaction. Dilute aqueous sodium (or potassium) hydroxide used in the electrolysis provides and movement of hydroxide ions to the anode to form oxygen. Alkaline water electrolysis utilizes two electrodes operating in a liquid alkaline electrolyte solution, usually potassium hydroxide (KOH). Next the iron half-reaction is considered. Like Copper, nickel can be refined by electrolysis. The diagram below shows an apparatus in which the electrolysis of aqueous sodium sulphate containing litmus solution was carried out.-When the current was passed through the solution, the solution around the anode turned red and . RT Hydrogen ions are a better choice. elements. For an electrode (half - cell) corresponding to the electrode reaction, Oxidised form ne Reduced form. Chris Beulah . Add 6 electrons to the left-hand side to give a net 6+ on each side. Combining the half-reactions to make the ionic equation for the reaction. 53.13 g of potassium hydroxide and 67.81 g of prussian blue is required. A: The unbalanced reaction is - Mg (HCO3)2 + CH3COOH + H2O = CO2 + H2O + Mg (CH3COO)2. The situation is more complicated when you electrolyse a solution rather than a melt because of the presence of the water. Reduction of Na + (E = -2.7 v) is energetically more difficult than the reduction of water (-1.23 v), so in aqueous solution, the latter will prevail. 6
The following half-reactions occur in the electrolysis of water: Oxidation half-reaction (anode) 2H 2 O(l) O 2 0 0. Electrolyzers can range in size from small, appliance-size equipment that is well . Exhibition chemistry Brew up interest in redox with this quick reduction. Electrolysis
(H 2 SO 4) and potassium hydroxide (KOH) with operating conditions range from 20 to 60 C (temperature), 1.98 to 2.2 V . . At the positive electrode (anode) chlorine gas is produced by the discharge of chloride ions: 2Cl- - 2e- Cl2 Oxidation. POTASSIUM HYDROXIDE, SOLUTION is a strong base dissolved in water. Potassium hydroxide solution is more conductive when compared to NaOH and therefore used as an electrolyte in some alkaline batteries. ( f ) (I) Add To Classified. Need Jan 2022 Past papers - Oxford AQA international A level CH03/CH04/Ch05, Chemistry alevel aqa amount of substance question. Write an equation for the half-reaction that occurs at this electrode. 1:59 (Triple only) write ionic half-equations representing the reactions at the electrodes during electrolysis and understand why these reactions are classified as oxidation or reduction . 6,258. chlorine atoms. Science Advisor. Now that all the atoms are balanced, only the charges are left. Write an equation for its formation. AQA Combined science: Synergy. All NH 4+ salts are soluble. The aim of this study is to select the best alloy for. Required equations: (Include state symbols and balance reactions if necessary) Iron (II) nitrate and potassium hydroxide solutions are combined. The health hazards of potassium hydroxide are similar to those of the other strong alkalies, such as sodium hydroxide. As some curricula do not include this type of problem, the process for balancing alkaline redox reactions is covered on a separate page. 4.4.3.5 Representation of reactions at electrodes as half equations (HT only) During electrolysis, at the cathode (negative electrode), positively charged ions gain electrons and so the reactions are reductions. Revision Questions, gcsescience.com
( f ) Add To Classified. So, initially the concentration-kinetic factor wins out, the much higher concentration of chloride ions . It is non-flammable but quite corrosive. 4.7.5 Atoms into ions and ions into . As the oxidizing agent, M anganate (VII) is reduced to manganese(II). The solution may be represented by K+(aq) and Cl(aq) At the positive electrode (anode) the following happens: ClCl +e. Potassium hydroxide is prepared at industrial scale by electrolysis of potassium chloride solution. Purity of 98% is the highest available for . The following electrolysis circuit is set up, using inert electrodes. The net equation which results is 3CH 3OH + 4MnO - 4 3HCOO - + 4MnO 2 + OH - Again, it is worthwhile to check that all atoms and charges balance. by | Jun 16, 2022 | baja telecaster vs american special | muslim population in spain in 2021 | Jun 16, 2022 | baja telecaster vs american special | muslim population in spain in 2021 2Cl Cl2(g) At the other side (cathode): K+ +e K. K + H 2O K+ + OH +H. Nitric acid (HNO3) and potassium hydroxide (KOH) react to form water and aqueous potassium nitrate (KNO3). This is easily resolved by adding two electrons to the left-hand side. This technique can be used just as well in examples involving organic chemicals. Aluminium is extracted by the electrolysis of molten aluminium oxide, Al 2 O 3. potassium hydroxide electrolysis half equation. 4. 45% potassium hydroxide. Electrolyzers using a liquid alkaline solution of sodium or potassium hydroxide as the electrolyte have been commercially available for many years. Potassium (KOH) hydroxide, commonly known as caustic potash, is the largest volume of potassium chemicals for non-fertilizer use. Chemistry Olympiad Prep 2023 - study buddy. The gas in the cathode is hydrogen. Reaction with Water. Electricity generation using renewable or nuclear energy technologies, either separate from the grid, or as a growing portion of the grid mix, is a possible option to overcome these limitations for hydrogen production via electrolysis. Electrolysis
Steam at the cathode combines with electrons from the external circuit to form hydrogen gas and negatively charged oxygen ions. . At the cathode, hydrogen ions combine with electrons from the external circuit to form hydrogen gas. The Periodic Table
5 electrons are added to the left-hand side to reduce the +7 to +2: \[ MnO_4^- + 8H^+ + 5e^- \rightarrow Mn^{2+} _ 4H_2O\nonumber \]. Like fuel cells, electrolyzers consist of an anode and a cathode separated by an electrolyte. pizza nostra karen gravano closed; what does the la choy symbol mean; mergest kingdom dragons den; bahnhof apotheke versand write a experimentel protocol for a practical in 1st personal does it matter ? See our example GCSE Essay on Chemistry revision notes. Reacts exothermically with all acids. It is used as a pH control agent in the food industry. (a) Hydrogen gas and hydroxide ion form at the cathode. In terms of attractive forces, explain why there is a large difference between these melting points, (potassium bromide): ionic bonds / attraction between ions, (iodine monochloride): intermolecular forces / forces between molecules / named intermolecular forces, e.g. If you need to know how to balance chemical reactions, see my complete tutorial on balancing all types of chemical equations:Balancing Equations in 5 Easy Steps: https://youtu.be/zmdxMlb88FsMore Practice Balancing: https://youtu.be/Qci7hiBy7EQDrawing/writing done in InkScape. Molten KBr under electrolysis will have the following half equations. Balance the equation for the reaction of hydroxide ions at the anode. The battery used to drive this reaction must therefore have a potential of at least 4.07 volts. It is used in the manufacturing of cuticle removers which are used in manicure treatment. . Done on a Dell Dimension laptop computer with a Wacom digital tablet (Bamboo).
Sie befinden sich hier: cosmetology school atlanta; what is the best definition of allegory? When chlorine gas is passed through aqueous potassium bromide, a redox reaction occurs The ionic equation is shown. Zn 2+ + 2e- Zn (zinc metal at the (-)cathode). The test for hydrogen gas is the burning splint test. ; During the electrolysis using carbon electrodes, The Cu 2+ ions and H + ions move to the cathode. The experiment I chose was to investigate the difference of time taken to produce 25mL of H2 gas in an electrolytic cell when the concentration of the potassium hydroxide electrolyte was changed. The role of water in the electrolysis of aqueous solutions of electrolytes. In the process, the chlorine is reduced to chloride ions. UN 1814: Potassium hydroxide, solution - HazMat Tool new www.hazmattool.com. What we have so far is: CH 3 CH 2 OH + H 2 O CH 3 COOH + 4H + + 4e -. In small concentration, the electrolysis of water becomes more predominant yielding hydrogen at cathode and oxygen at the anode. 2K (potassium
What to even say? 0 2. Subtracting 10 hydrogen ions from both sides leaves the simplified ionic equation. The potassium ions will be in solid phase at the cathode. To give a different example, here is a half-reaction involving lead: $$\ce{Pb(s) + HSO4^-(aq)-> PbSO4(s) + H+(aq) + 2e-}$$ . Water electrolysis outruns the performance of most other conventional techniques, which involve two half-reactions, namely hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) [10]. potassium hydroxide electrolysis half equation . Hydrogen fuel for cars? It can be made by the electrolysis of potassium hydroxide solution. Electrolysis separates the molten ionic compound into its elements. gain
2H H 2(g) So the net result is that at the anode chlorine gas is released, at the cathode hydrogen gas is released, and a . Chronic exposure: repeated contact with dilute solutions of potassium hydroxide dust has a tissue-destroying effect. To start a Business, what do I do? The atoms in the equation must be balanced: \[\ce{ Cl_2 \rightarrow 2Cl^{-}}\nonumber \]. potassium atoms. Chlorine and Hydrogen are formed from the electrolytic production as co-products. To balance these, eight hydrogen ions are added to the left: \[ MnO_4^- + 8H^+ \rightarrow Mn^{2+} + 4H_2O\nonumber \]. Select the correct answer and click on the Finish buttonCheck your score and answers at the end of the quiz, Visit BYJUS for all Chemistry related queries and study materials, Your Mobile number and Email id will not be published. The equation for KOH (Potassium hydroxide) and H2O sometimes isnt considered a chemical reaction since it is easy to change the K+ and OH- back to KOH (just let the H2O evaporate). Electrolysis-Past papers questions 49. Balance the atoms apart from oxygen and hydrogen. Electrolysis is a promising option for carbon-free hydrogen production from renewable and nuclear resources. No characteristic odour can be attributed to this compound in its solid state. Electrolysis of concentrated sodium chloride solutions (brine) produces chlorine gas, hydrogen gas and aqueous sodium hydroxide. Hydrogen is an excellent fuel. It is used in chip fabrication for semiconductors. The half-reactions are given below. Required fields are marked *. Electrolysis of Zinc Chloride.. Zinc can be extracted from zinc oxide by heating with carbon or from zinc chloride by electrolysis.. Zinc chloride must be heated until it is molten before it will conduct electricity.Electrolysis separates the molten ionic compound into its elements. Iron (II) ions are oxidized to iron (III) ions as shown: Fe 2 + Fe 3 + The atoms balance, but the charges do not. Bonds, Structure & Properties of Matter, 2.4.1 Sizes of Particles & their Properties, 3.1.1 Conservation of Mass & Balanced Chemical Equations, 3.1.3 Mass Changes when a Reactant or Product is a Gas, 3.5.1 Amount of Substance in Relation to Volumes of Gases, 4.1.4 Oxidation & Reduction in Terms of Electrons, 4.2.2 Metal & Acid Reactions as Redox Reactions, 4.2.3 Neutralisation of Acids and Salt Production, 4.2.5 Required Practical: Preparation of a Soluble Salt, 4.2.9 Required Practical: Strong Acid & Strong Alkali Titration, 4.3.2 Electrolysis of Molten Ionic Compounds, 4.3.3 Using Electrolysis to Extract Metals, 4.3.5 Required Practical: Electrolysis of Aqueous Solutions, 5.1.2 Required Practical: Investigating Temperature Changes, 5.2.3 Electrode Reactions in Hydrogen Fuel Cells, 6.1.5 Factors that Affect the Rate of Reaction, 6.1.6 Required Practical: Investigating the Effect of Concentration on Rate of Reaction, 6.1.7 Collision Theory & Activation Energy, 6.2.2 Energy Changes & Reversible Reactions, 6.2.4 The Effect of Changing Conditions on Equilibrium, 6.2.5 The Effect of Changing Concentration, 6.2.6 The Effect of Temperature Changes on Equilibrium, 6.2.7 The Effect of Pressure Changes on Equilibrium, 7.1.2 Fractional Distillation & Petrochemicals, 8.1 Purity, Formulations & Chromatography, 8.1.4 Required Practical: Investigating Chromatography, 8.3.6 Required Practical: Identifying Ions, 9.2.4 The Carbon Footprint & Its Reduction, 9.3.2 Properties & Effects of Atmospheric Pollutants, 10.1.3 Required Practical: Analysis & Purification of Water Samples, 10.1.5 Alternative Methods of Extracting Metals, In electrochemistry we are mostly concerned with the, As the ions come into contact with the electrode, electrons are either lost or gained and they form, At the anode, negatively charged ions lose electrons and are thus, At the cathode, the positively charged ions gain electrons and are thus, This can be illustrated using half equations which describe the movement of electrons at each electrode. Here, we prepared a metal-organic framework (MOF) through a simple hydrothermal reaction. Deduce the products of the electrolysis of a molten saltElectrolysis of a molten salt produces the elements from the salt.So, the electrolysis of WCl4 produces W and Cl2. Electrolysis is a promising option for carbon-free hydrogen production from renewable and nuclear resources. 1955]. Chlorine and hydrogen are byproducts of this . 2023-01-23T10:00:00Z. Hypokalemia (low potassium) or hyperkalemia (high potassium) may result, At the cathode, water is reduced to hydrogen and oxide ions.