list four properties shared by the halogens

Answer 1

1. All halogens have seven electrons in their outermost shell.
2. They are highly reactive and tend to form compounds with other elements.
3. Halogens have a negative oxidation state of -1.
4. They exist in all three states of matter at room temperature: fluorine and chlorine are gases, bromine is a liquid, and iodine is a solid.