CORE Chemistry (Short Course) - 9222 OxfordAQA

Redox Reactions

Gbogbo ọrọ náà

A furnace in Nigeria, Brazil or China spends its whole working life pulling oxygen off iron ore, and the moment the finished steel leaves the mill the air begins putting that oxygen back. Extraction and corrosion look like completely unrelated pieces of chemistry. They are the same process running in opposite directions, and once you can see that, a large part of this course stops being a list of separate reactions and turns into one idea wearing different clothes.

That idea is redox, and this specification gives you a single, very portable test for spotting it: follow the oxygen. A substance that finishes with more oxygen than it started with has been oxidised, one that finishes with less has been reduced, and any reaction where both of those are going on at once is a redox reaction. You will finish this lesson able to take an equation you have never seen before, decide in under a minute which substance was oxidised and which was reduced, and say exactly how you know.

Ebumnobi

  1. Oxidation can be described as the gain of oxygen by a substance and reduction as the loss of oxygen from a substance. Students should be able to describe chemical reactions within this specification in terms of oxidation and reduction using the definitions above.
  2. When oxidation and reduction are happening at the same time this is known as a redox reaction, for example: Fe2O3 + 3 CO 2 Fe + 3 CO2 Oxidation

Maapụ uche

E seela isiokwu a ka ị hụ otu echiche si ejikọta.

Mepee maapụ uche na ngwa

Akwụkwọ Ọmụmụ

Iron does not occur in the ground as iron. It occurs as iron(III) oxide, a red-brown rock in which every iron atom is already locked to oxygen. Getting metal out of it means stripping that oxygen away, and a furnace is essentially a very large, very hot machine built to do exactly that. The furnace wins. Then the beam, the bridge or the gate goes out into damp air, and over the following years the oxygen quietly walks back in. The orange crust that forms is iron(III) oxide again. A whole industry of galvanising, painting, greasing and electroplating exists to slow down a reaction that is simply the reverse of the one the furnace was built to force.

Ndetu Nkuzi Zuru Ezu di na Ngwa Green Bridge

Nweta ngwa Green Bridge CBT na ekwenti gi ma o bu kompiuta maka ulo akwukwo IGCSE zuru oke: akwukwo ule ndi gara aga, usoro nyocha, eserese uche, kaadi omumu na nkuzi olu.

Akwụkwọ ndụmọdụ zuru oke nwere eserese
Onye inyeaka mmụta AI
Ule nnwale nwere oge a na-ahazi ozugbo i mechara
Ọ dị na Android, Windows, macOS, na Linux Ngwa iOS na-abia n'oge na-adighi anya

Nnyocha Ọmụmụ

Ekele diri gi maka imecha ihe karịrị na Redox Reactions. Ugbu a na ị na-enyochakwa isi echiche na echiche ndị dị mkpa, ọ bụ oge iji nwalee ihe ị ma. Ngwa a na-enye ụdị ajụjụ ọmụmụ dị iche iche emebere iji kwado nghọta gị wee nyere gị aka ịmata otú ị ghọtara ihe ndị a kụziri.

Ị ga-ahụ ngwakọta nke ụdị ajụjụ dị iche iche, gụnyere ajụjụ chọrọ ịhọrọ otu n’ime ọtụtụ azịza, ajụjụ chọrọ mkpirisi azịza, na ajụjụ ede ede. A na-arụpụta ajụjụ ọ bụla nke ọma iji nwalee akụkụ dị iche iche nke ihe ọmụma gị na nkà nke ịtụgharị uche.

Jiri akụkụ a nke nyocha ka ohere iji kụziere ihe ị matara banyere isiokwu ahụ ma chọpụta ebe ọ bụla ị nwere ike ịchọ ọmụmụ ihe ọzọ. Ekwela ka nsogbu ọ bụla ị na-eche ihu mee ka ị daa mba; kama, lee ha anya dị ka ohere maka ịzụlite onwe gị na imeziwanye.

  1. Which of these describes oxidation? A. the gain of oxygen by a substance B. the loss of oxygen from a substance C. a rise in the temperature of a substance D. the formation of a precipitate Answer: A
  2. In the reaction Fe2O3 + 3 CO -> 2 Fe + 3 CO2, which substance is oxidised? A. Fe2O3 B. CO C. Fe D. CO2 Answer: B
  3. Zinc oxide is heated with carbon: 2 ZnO + C -> 2 Zn + CO2. Which substance is reduced? A. carbon B. zinc C. zinc oxide D. carbon dioxide Answer: C
  4. Which statement about a redox reaction is correct? A. Oxidation happens first and reduction happens afterwards. B. Only reactions that involve a metal can be redox reactions. C. Oxidation and reduction take place at the same time. D. A substance that is reduced always ends up with a smaller mass. Answer: C
  5. Carbon dioxide is passed over hot carbon: CO2 + C -> 2 CO. Which statement is correct? A. Carbon is reduced and carbon dioxide is oxidised. B. Carbon is oxidised and carbon dioxide is reduced. C. Neither substance is oxidised or reduced, because both contain carbon. D. Both substances are oxidised. Answer: B

Rue ajuju ndi a n'ime ngwa ahu

Rue ajuju ndi a n'ime ngwa ahu

Meecha Ajụjụ Ule Ọmarịcha

Ị chọrọ ime ajụjụ ule ọmarịcha gbasara Redox Reactions? Budata ngwa Green Bridge CBT iji nweta ajụjụ ule ọmarịcha na nyocha zuru ezu gbasara isiokwu a.

Budata Ngwa Ahụ Na Google Playstore

Ihe nile ichoro iji nwee ihe ịga nke ọma na JAMB, WAEC & NECO.

Green Bridge CBT Mobile App
Onye Enyemaka Nkata AI Nke Ọmụmụ Ihe Ahaziri Maka Gị
Ajụjụ ule IGCSE, JAMB, WAEC na NECO karịrị 200,000
Ihe karịrị 1200 Nkọwa Nkuzi
Nkwado Na-enweghị Ịntanetị - Mụọ Ihe Mgbe Ọ Bụla, Ebe Ọ Bụla
Jadawalin Gada Kore
Akọkọ akọle iwe & Ibeere agbara
Sọfụma Ọrụ Gi & Ọganihu Gi
Nkọwa Miri Emi Maka Ọmụmụ Ihe Zuru Ezu