[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"doc-detail-207965-en":3,"doc-seo-207965-105":30,"detail-sidebar-cat-0-en-105":91},{"code":4,"msg":5,"data":6},0,"success",{"doc_id":7,"user_id":8,"nickname":9,"user_avatar":10,"doc_module":4,"category_id":11,"category_name":12,"doc_title":13,"doc_description":14,"doc_content":15,"file_id":16,"file_url":17,"file_type":18,"file_size":19,"view_count":20,"is_deleted":4,"is_public":20,"is_downloadable":20,"audit_status":20,"page_count":21,"language":22,"language_code":23,"site_id":24,"html_lang":23,"table_of_contents":25,"faqs":26,"seo_title":27,"seo_description":14,"update_tm":28,"read_time":29},207965,962084925290,"Caleb Sterling","https://ap-avatar.wpscdn.com/davatar_085a072bc5b1113ac321206ff7593b45",4,"Exam","GCSE Chemistry - Unit 2.7 - Electrochemistry","GCSE Chemistry Unit 2.7 focuses on electrochemistry through clear definitions and core ideas about electrolysis and ionic conduction. Learners explain electrolysis, inert electrodes, anodes, cathodes, and how ions move to carry charge. The unit predicts products and observations for electrolysis of molten salts such as lithium chloride and lead(II) bromide, then interprets and writes half equations for anode and cathode reactions. It also covers industrial extraction of aluminium from alumina using cryolite, including purification of bauxite and periodic anode replacement, and the reduced energy and environmental impact of recycling aluminium.","FACTFILE:  \nGCSE DAS CHEMISTRY:  \nUNIT 2.7  \nElectrochemistry  \nLearning outcomes:  \n2.7.1 explain the meaning of the terms electrolysis, inert electrode, anode, cathode and electrolyte and explain conduction in an electrolyte in terms of ions moving and carrying charge;  \n2.7.2 predict the products of electrolysis of molten salts including lithium chloride and lead(II) bromide using graphite electrodes and state appropriate observations at the electrodes;  \n2.7.3 interpret and write half equations for the reactions occurring at the anode and cathode for the electrolysis processes listed in 2.7.2, for other molten halides and in the extraction of aluminium;  \n2.7.4 describe the industrial extraction of aluminium from alumina and demonstrate knowledge and understanding that the alumina has been purified from the ore bauxite and demonstrate knowledge and understanding of the need to replace the anodes periodically;  \n2.7.5 demonstrate knowledge and understanding that recycling aluminium uses only a fraction of the energy needed to extract it from bauxite and saves waste.  \nElectrolysis  \nThe term electrolysis can be split to aid understanding – ‘electro’ refers to electricity and ‘lysis’ refers to breaking down.  \nThere are a number of key definitions required for this topic:  \nElectrolysis – the decomposition of a liquid electrolyte using a direct current of electricity.  \nElectrolyte – an ionic compound that is molten or dissolved in water that conducts electricity and is decomposed by it.  \nInert electrode – an unreactive material which can conduct electricity usually graphite or platinum. Cathode – the negative electrode (attached to the negative terminal of the battery) .  \nAnode – the positive electrode (attached to the positive terminal of the battery) .  \nFACTFILE: GCSE CHEMISTRY : UNIT 2.7  \nApparatus for electrolysis of a molten compound  \nThe electrolytes are molten ionic compounds and can conduct electricity as the ions are free to move and carry charge. The positive ions (cations) are attracted to cathode and gain electrons to form atoms or molecules – gain of electrons is reduction. The negative ions (anions) are attracted to the anode and lose electrons to form atoms or molecules – loss of electrons is oxidation.  \nThe table below summarises the observations and half equations for two named ionic compounds:  \n| MOLTEN IONIC COMPOUND | Lead(II) bromide | Lithium chloride |\n| --- | --- | --- |\n| Anode observation | red-brown vapour pungent smell | yellow-green vapour pungent smell |\n| Anode half equation | 2Br ~~ ~~ Br2 + 2e– | 2Cl– ~~ ~~ Cl2 + 2e– |\n| Cathode observation | silver grey metallic bead | silver grey metallic bead |\n| Cathode half equation | Pb2 + 2e– ~~ ~~ Pb | Li + + e– ~~ ~~ Li |\n\n2  \nFACTFILE: GCSE CHEMISTRY : UNIT 2.7  \nExtraction of aluminium from its ore by electrolysis  \nAluminium is one of the more reactive metals and hence its extraction must come from the process of electrolysis. The ore from which aluminium is extracted is called bauxite. Bauxite is a red mineral made of aluminium oxide and iron oxides and is mined in various places such as Russia and Jamaica. The bauxite must be purified before undergoing electrolysis.  \nThe steps in the purification process are:  \n1. It is heated with sodium hydroxide, this dissolves the alumina but not the other minerals.  \n2. The residue is filtered off and disposed of.  \n3. The filtrate is acidified and heated to produce pure alumina, aluminium oxide powder. The electrolytic cell used in the extraction of aluminium.  \ncarbon anodes  \ncrust of aluminium oxide  \nsteel tank  \nMolten electrolyte (aluminium oxide dissolved in cryolite)  \nMolten  \ntapping hole to  \nremove molten aluminium  \naluminium Insulation  \ncarbon lining of cell (cathode)  \nThe alumina obtained from the purification has a very high melting point around 2050°C. This is too high a temperature to make the process economically viable so it is dissolved in molten cryolite which reduces the t","cbCaihw9aV1a6tEL","https://ap.wps.com/l/cbCaihw9aV1a6tEL","pdf",410356,1,6,"English","en",105,"# Learning outcomes\n## Electrolysis definitions and ionic conduction\n## Electrolysis of molten salts (lead(II) bromide, lithium chloride)\n## Extraction of aluminium from alumina\n## Reactions at the electrodes\n## Recycling of aluminium\n## Revision questions","[{\"question\":\"What is electrolysis and how does an electrolyte conduct electricity?\",\"answer\":\"Electrolysis is the decomposition of a liquid electrolyte using a direct current. An electrolyte conducts because it contains ions that are free to move and carry charge.\"},{\"question\":\"What happens at the anode and cathode during electrolysis of molten lithium chloride and molten lead(II) bromide?\",\"answer\":\"At the cathode, metal forms as electrons are gained and reduction occurs, while at the anode electrons are lost and oxidation occurs. For molten lithium chloride, chlorine gas forms at the anode and lithium forms at the cathode; for lead(II) bromide, bromine forms at the anode and lead forms at the cathode.\"},{\"question\":\"How is aluminium extracted from alumina and why must the carbon anodes be replaced?\",\"answer\":\"Alumina is purified from bauxite, then dissolved in molten cryolite to reduce the melting temperature. Oxygen produced at the anode reacts with the graphite carbon anode, so the anodes burn away and require periodic replacement.\"}]","GCSE Chemistry - Unit 2.7 - Electrochemistry | PDF",1788601928,15,{"code":4,"msg":31,"data":32},"ok",{"site_id":24,"language":23,"slug":33,"title":13,"keywords":34,"description":14,"schema_data":35,"social_meta":86,"head_meta":88,"extra_data":90,"updated_unix":28},"gcse-chemistry-unit-27-electrochemistry","",{"@graph":36,"@context":85},[37,53,68],{"@type":38,"itemListElement":39},"BreadcrumbList",[40,44,48,51],{"item":41,"name":42,"@type":43,"position":20},"https://docshare.wps.com","Home","ListItem",{"item":45,"name":46,"@type":43,"position":47},"https://docshare.wps.com/document/","Document",2,{"item":49,"name":12,"@type":43,"position":50},"https://docshare.wps.com/document/exam/",3,{"item":52,"name":13,"@type":43,"position":11},"https://docshare.wps.com/document/gcse-chemistry-unit-27-electrochemistry/207965/",{"url":52,"name":13,"@type":54,"author":55,"headline":13,"publisher":57,"fileFormat":60,"inLanguage":23,"description":14,"dateModified":61,"datePublished":62,"encodingFormat":60,"isAccessibleForFree":63,"interactionStatistic":64},"DigitalDocument",{"name":9,"@type":56},"Person",{"url":41,"name":58,"@type":59},"DocShare","Organization","application/pdf","2026-09-06","2026-09-05",true,{"@type":65,"interactionType":66,"userInteractionCount":20},"InteractionCounter",{"@type":67},"ViewAction",{"@type":69,"mainEntity":70},"FAQPage",[71,77,81],{"name":72,"@type":73,"acceptedAnswer":74},"What is electrolysis and how does an electrolyte conduct electricity?","Question",{"text":75,"@type":76},"Electrolysis is the decomposition of a liquid electrolyte using a direct current. An electrolyte conducts because it contains ions that are free to move and carry charge.","Answer",{"name":78,"@type":73,"acceptedAnswer":79},"What happens at the anode and cathode during electrolysis of molten lithium chloride and molten lead(II) bromide?",{"text":80,"@type":76},"At the cathode, metal forms as electrons are gained and reduction occurs, while at the anode electrons are lost and oxidation occurs. For molten lithium chloride, chlorine gas forms at the anode and lithium forms at the cathode; for lead(II) bromide, bromine forms at the anode and lead forms at the cathode.",{"name":82,"@type":73,"acceptedAnswer":83},"How is aluminium extracted from alumina and why must the carbon anodes be replaced?",{"text":84,"@type":76},"Alumina is purified from bauxite, then dissolved in molten cryolite to reduce the melting temperature. Oxygen produced at the anode reacts with the graphite carbon anode, so the anodes burn away and require periodic replacement.","https://schema.org",{"og:url":52,"og:type":87,"og:title":13,"og:site_name":58,"og:description":14},"article",{"robots":89,"canonical":52},"index,follow",{"doc_id":7,"site_id":24},{"code":4,"msg":5,"data":92},[93,97,101,104,109,113,118,123,128,131,135],{"id":20,"doc_module":4,"doc_module_name":46,"category_name":94,"show_sort_weight":95,"slug":96},"Story & Novel",90,"story-novel",{"id":47,"doc_module":4,"doc_module_name":46,"category_name":98,"show_sort_weight":99,"slug":100},"Literature",80,"literature",{"id":11,"doc_module":4,"doc_module_name":46,"category_name":12,"show_sort_weight":102,"slug":103},70,"exam",{"id":105,"doc_module":4,"doc_module_name":46,"category_name":106,"show_sort_weight":107,"slug":108},5,"Comic",60,"comic",{"id":21,"doc_module":4,"doc_module_name":46,"category_name":110,"show_sort_weight":111,"slug":112},"Technology",50,"technology",{"id":114,"doc_module":4,"doc_module_name":46,"category_name":115,"show_sort_weight":116,"slug":117},7,"Healthcare",40,"healthcare",{"id":119,"doc_module":4,"doc_module_name":46,"category_name":120,"show_sort_weight":121,"slug":122},8,"Research & Report",30,"research-report",{"id":124,"doc_module":4,"doc_module_name":46,"category_name":125,"show_sort_weight":126,"slug":127},9,"Religion & Spirituality",20,"religion-spirituality",{"id":126,"doc_module":4,"doc_module_name":46,"category_name":129,"show_sort_weight":126,"slug":130},"World Cup","world-cup",{"id":132,"doc_module":4,"doc_module_name":46,"category_name":133,"show_sort_weight":132,"slug":134},10,"Lifestyle","lifestyle",{"id":136,"doc_module":4,"doc_module_name":46,"category_name":137,"show_sort_weight":105,"slug":138},19,"General","general"]