The halogens, the elements of family 17 on the periodic table, combine easily with elements from family 1. when a halogen reacts with a metal, what type of compound is formed?

When halogen elements react with group one metals they form halide salts.

Explanation:

The elements of group 17 are called halogens. These are six elements Fluorine, Chlorine, Bromine, Iodine, Astatine. Halogens are very reactive these elements can not be found free in nature. Their chemical properties are resemble greatly with each other. As we move down the group in periodic table size of halogens increases that's way fluorine is smaller in size as compared to other halogens elements. Their boiling points also increases down the group which changes their physical states. i.e fluorine is gas while iodine is solid.

When halogen elements react with group one metals they form halide salts.

Alkali metals have one valance electron and halogens needed one electron to complete the octet thus alkali metals loses one electron which is accepted by halogens atom and form ionic compound called halide salts.

For example:

2Na + Cl₂ → 2NaCl

2K + Cl₂  → 2KCl

2Rb + Cl₂ → 2RbCl

2Li + Cl₂ → 2LiCl

With bromine:

2Na + Br₂ → 2NaBr

2K + Br₂  → 2KBr

2Rb + Br₂ → 2RbBr

2Li + Br₂ → 2LiBr

With iodine:

2Na + I₂ → 2NaI

2K +  I₂ → 2KBI

2Rb + I₂ → 2RbI

2Li + I₂ → 2LiI

i do not get it   at all