Corrosion Of Metals
Gbogbo ọrọ náà
Every year, vast sums are spent replacing iron and steel that has crumbled into orange-brown rust. Rusting is a slow chemical attack that needs just two things from the environment, and once you know what they are, you know how to stop it. Protecting metal from corrosion is one of the most practical applications of chemistry.
In this lesson you will learn the conditions needed for iron to rust, the barrier methods that keep it dry and airtight, and the clever use of a more reactive metal in galvanising and sacrificial protection. You will explain sacrificial protection in terms of the reactivity series and the loss of electrons.
Ebumnobi
- State the conditions required for the rusting of iron and steel to form hydrated iron(III) oxide.
- State some common barrier methods, including painting, greasing and coating with plastic.
- Describe how barrier methods prevent rusting by excluding oxygen or water.
- [Supplement] Describe the use of zinc in galvanising as an example of a barrier method and sacrificial protection.
- [Supplement] Explain sacrificial protection in terms of the reactivity series and in terms of electron loss.
Akọmọ Ojú-ẹkọ
Ọ dị na ngwa Green Bridge
Budata ngwa Green Bridge CBT na ekwentị maọbụ kọmputa gị iji nweta akwụkwọ ndụmọdụ zuru oke, ajụjụ mmụta, na ndị ọzọ.
Ayẹwo Ẹkọ
Ekele diri gi maka imecha ihe karịrị na Corrosion Of Metals. 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.
- Which two substances are needed for iron to rust? A. oxygen and carbon dioxide B. water and oxygen C. water and nitrogen D. salt and oxygen only Answer: B
- Rust is mainly: A. iron(II) oxide B. hydrated iron(III) oxide C. iron carbonate D. iron sulfide Answer: B
- Which is a barrier method of rust prevention? A. galvanising B. sacrificial protection C. painting D. attaching magnesium blocks Answer: C
- In sacrificial protection of iron, the metal used must be: A. less reactive than iron B. more reactive than iron C. a non-metal D. the same as iron Answer: B
- Galvanising protects steel by: A. only acting as a barrier B. only sacrificial protection C. acting as a barrier and by sacrificial protection D. making the steel more reactive Answer: C
Ọ dị na ngwa Green Bridge
Budata ngwa Green Bridge CBT na ekwentị maọbụ kọmputa gị iji nweta akwụkwọ ndụmọdụ zuru oke, ajụjụ mmụta, na ndị ọzọ.
Ọ dị na ngwa Green Bridge
Budata ngwa Green Bridge CBT na ekwentị maọbụ kọmputa gị iji nweta akwụkwọ ndụmọdụ zuru oke, ajụjụ mmụta, na ndị ọzọ.
Àwọn Ìwé Tó Dáa Láti Kà
Meecha Ajụjụ Ule Ọmarịcha
Ị chọrọ ime ajụjụ ule ọmarịcha gbasara Corrosion Of Metals? Budata ngwa Green Bridge CBT iji nweta ajụjụ ule ọmarịcha na nyocha zuru ezu gbasara isiokwu a.
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