The Group 7 elements are known as the halogens.
The table below shows information about some of the halogens.
| Name | Atomic number | Melting point (∘C^\circ\text{C}∘C) | State at room temperature (20∘C20\circ\text{C}20∘C) | Chemical symbol |
|---|---|---|---|---|
| Chlorine | 17 | -101 | Gas | Cl\text{Cl}Cl |
| Bromine | 35 | -7 | Liquid | Br\text{Br}Br |
| Iodine | 53 | 114 | Solid | I\text{I}I |
Which is the most reactive halogen in the table?
Astatine is also a halogen. It has the chemical symbol At\text{At}At and an atomic number of 85.
Look at the table.
Predict the state of astatine at 100∘C100^\circ\text{C}100∘C.
Predict the melting point of astatine.
Lithium, Li\text{Li}Li, reacts with bromine. A white solid is made.
What is the name of this white solid?
Write down the balanced symbol equation for this reaction.