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Group 7(17), the halogens key terms
Use these key terms for Group 7(17), the halogens in AQA Chemistry 7405. The page is built from approved learning objectives for this topic and links back to the wider unit, topic hub, and related revision assets.
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key terms
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Group 7(17), the halogens
Key terms
Electronegativity
A measure of the tendency of an atom to attract a bonding pair of electrons. In Halogen trends and displacement, Electronegativity is used to explain describe trends in electronegativity and boiling point down Group 7 with A-Level Chemistry precision.
Boiling Point
The temperature at which a substance changes from a liquid to a gas at a given pressure.
oxidising ability
The tendency of a substance to gain electrons and thereby be reduced in a chemical reaction.
halogens
Elements in Group 7 of the periodic table, known for their high electronegativity and reactivity, particularly in oxidation reactions.
halogen displacement reaction
A chemical reaction where a more reactive halogen displaces a less reactive halogen from its compound.
oxidising ability
The tendency of a substance to gain electrons and be reduced, which increases down Group 7 for halogens.
halogen displacement reaction
A chemical reaction where a more reactive halogen displaces a less reactive halogen from its compound.
ionic equation
A representation of a chemical reaction that shows the ions involved and their charges, highlighting the species that undergo change.
Halide ion test
A qualitative analysis method to identify halide ions by adding silver nitrate, resulting in a precipitate.
Silver nitrate reaction
The reaction of silver nitrate with halide ions to form a colored precipitate, indicating the presence of specific halides.
chlorine
A chemical element (Cl) used in water treatment to kill bacteria and other pathogens. In Halide ions and uses of chlorine, chlorine is used to explain explain the use of chlorine in water treatment with A-Level Chemistry precision.
water treatment
The process of making water safe for drinking and other uses, often involving the addition of chlorine.
disproportionation reaction
A reaction in which a single substance is both oxidized and reduced, resulting in the formation of two different products.
chlorine in water treatment
The use of chlorine to disinfect water by killing bacteria and other pathogens, ensuring safe drinking water.
chlorine benefits
Chlorine is effective in killing bacteria and pathogens in water, making it safe for drinking and swimming.
chlorine risks
Chlorine can produce harmful byproducts, such as chlorinated hydrocarbons, which may pose health risks.