Group 7 (halogens)
Gbogbo ọrọ náà
The halogens sit in Group 7 of the periodic table and include some of the most recognisable non-metals in chemistry. Chlorine disinfects swimming pools, bromine is one of only two elements that are liquid at room temperature, and iodine is the dark solid used to test for starch. Despite looking very different, all halogens share a pattern of chemical behaviour because they each have seven electrons in their outer shell.
In this lesson you will learn the physical properties and trends across Group 7, explore how displacement reactions reveal the reactivity trend, and practise predicting the properties of halogens you may not have met.
Ebumnobi
- Know the colours, physical states (at room temperature) and trends in physical properties of these elements
- Use knowledge of trends in Group 7 to predict the properties of other halogens
- Understand how displacement reactions involving halogens and halides provide evidence for the trend in reactivity in Group 7
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 Group 7 (halogens). 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.
- What is the physical state of bromine at room temperature? A) Solid B) Liquid C) Gas D) Plasma Answer: B
- Which halogen is the most reactive? A) Iodine B) Bromine C) Chlorine D) Fluorine Answer: D
- What colour change is seen when chlorine water is added to potassium bromide solution? A) Colourless to brown B) Colourless to orange C) Orange to colourless D) Brown to colourless Answer: B
- Why does reactivity decrease down Group 7? A) The atoms lose electrons more easily B) The atoms have fewer electrons in their outer shell C) The outer shell is further from the nucleus, weakening the attraction for incoming electrons D) The atoms become smaller Answer: C
- Which of the following displacement reactions would NOT occur? A) Chlorine added to potassium iodide B) Bromine added to potassium iodide C) Iodine added to potassium bromide D) Chlorine added to potassium bromide 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 Group 7 (halogens)? Budata ngwa Green Bridge CBT iji nweta ajụjụ ule ọmarịcha na nyocha zuru ezu gbasara isiokwu a.
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