Group 7 Flashcards
What is another name for group 7?
Halogens
What does group 7 want to do about its electrons?
Gain 1 electron
What are group 7’s appearances at room temperature?
- Chlorine = green gas
- Bromine = brown liquid
- Iodine = purple / black solid
What type of molecules is group 7?
Diatomic molecules
What are diatomic molecules?
Two atoms held together by a single covalent bond
What are group 7’s properties?
- Poor conductors of heat and electricity
- Toxic
- Corrosive
What do halogens form when reacted with metals?
- ionic compounds
- salts that contain halide
What do halogens form when reacted with hydrogen?
- hydrogen halides
What happens to hydrogen halides when dissolved in water?
They form acidic solutions
What uses are there for group 7?
- Sodium chloride = table salt
- Sodium flouride = found in toothpaste
- Sodium bromine - disinfectant for swimming pools
What can all halogen be used as?
- disinfectants
- bleaches
Why can halogens be used for bleaches and disinfectants?
Because they can kill microorganisms and remove colours from materials
What is the test for chlorine?
Damp blue litmus paper is placed in chlorine gas
- 1st turns red
THEN
- bleaches white
