testing for Halides

What is a halide?

A compounds formed when a halogen gains one electron to form a negative ion

A _____ is a compound formed when a halogen ___ one electron to form a negative ion.

Halide, gains

Give an example of a halogen becoming a halide

Chlorine—> Chloride (Cl-)

Give three examples of halides

Chloride

Bromide

Iodide

What do we use to test for halides

acidified silver nitrate solution

Describe a test to identify chloride ions and give the results

Add acidified silver nitrate, should produce a white precipitate

When testing for chloride ions, what colour precipitate should be produced?

White

When resting for bromide ions, what colour precipitate should be produced?

Cream

When testing for iodide ions, what colour precipitate should be produced?

Yellow

What would the symbol equation be when testing for chloride ions?

Ag⁺(aq) + Cl⁻(aq) → AgCl(s)

What would the symbol equation be when testing for Bromide ions?

Ag⁺(aq) + Br⁻(aq) → AgBr(s)

What would the symbol equation be when testing for Iodide ions?

Ag⁺(aq) + I⁻(aq) → AgI(s)

Silver iodide is…

Yellow

Silver chloride is…

White

Silver bromide is…

Cream

The halogens are the elements in Group __ of the periodic table

7

Halogens exist as ______ molecules and form negative ions (_____ ions) when they react

Diatomic, halide

Going down group 7, the reactivity….

Decreases