Group 7 (halogens)
Muhtasari
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.
Malengo
- 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
Maelezo ya Somo
Inapatikana kwenye programu ya Green Bridge
Pakua programu ya Green Bridge CBT kwenye simu yako au kompyuta yako ili kupata maelezo kamili ya masomo, maswali ya mazoezi, na mengi zaidi.
Tathmini ya Somo
Hongera kwa kukamilisha somo la Group 7 (halogens). Sasa kwa kuwa umechunguza dhana na mawazo muhimu, ni wakati wa kuweka ujuzi wako kwa mtihani. Sehemu hii inatoa mazoezi mbalimbali maswali yaliyoundwa ili kuimarisha uelewaji wako na kukusaidia kupima ufahamu wako wa nyenzo.
Utakutana na mchanganyiko wa aina mbalimbali za maswali, ikiwemo maswali ya kuchagua jibu sahihi, maswali ya majibu mafupi, na maswali ya insha. Kila swali limebuniwa kwa umakini ili kupima vipengele tofauti vya maarifa yako na ujuzi wa kufikiri kwa makini.
Tumia sehemu hii ya tathmini kama fursa ya kuimarisha uelewa wako wa mada na kubaini maeneo yoyote ambapo unaweza kuhitaji kusoma zaidi. Usikatishwe tamaa na changamoto zozote utakazokutana nazo; badala yake, zitazame kama fursa za kukua na kuboresha.
- 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
Inapatikana kwenye programu ya Green Bridge
Pakua programu ya Green Bridge CBT kwenye simu yako au kompyuta yako ili kupata maelezo kamili ya masomo, maswali ya mazoezi, na mengi zaidi.
Inapatikana kwenye programu ya Green Bridge
Pakua programu ya Green Bridge CBT kwenye simu yako au kompyuta yako ili kupata maelezo kamili ya masomo, maswali ya mazoezi, na mengi zaidi.
Vitabu Vinavyopendekezwa
Fanya Mazoezi ya Maswali ya Majaribio
Ungependa kufanya mazoezi ya maswali ya majaribio kuhusu Group 7 (halogens)? Pakua programu ya Green Bridge CBT ili kupata maswali ya majaribio na tathmini kamili za mazoezi kuhusu mada hii.
Pakua Programu Kwenye Google Playstore
Kila kitu unachohitaji ili kufaulu katika JAMB, WAEC & NECO.
