What are three halogens and describe a property that they all share?

Sep 18, 2017

All halogens are non-metals with seven valence electrons.

Explanation:

Halogens are elements that belong to group VII. They exist as diatomic molecules.

Properties:

• Melting and boiling points increases down the group.
• Halogens form molecular crystals thus their melting points are low
• Halogens are slightly soluble in polar solvents, e.g. $\text{H"_2"0}$
• Halogens are very soluble in non-polar organic solvents, e.g. $\text{CCl"_4, "C"_2"H"_5"OH}$
• In a chemical reaction, these non-metals gain an electron to form a univalent negative ion with -1 charge
• Chemical reactivity of the elements decreases down the group, fluorine being the most reactive and astatine being the least reactive.