Question

Bromine reacts with this metal at a particular rate. For every metal, two bromines attach to it. You collect other metals within that family and it still reacts at that same ratio. 2 bromines for every 1 metal. Why is that so?

Answer 1

The ratio of two bromines for every one metal occurs because halogens like bromine form anions with a charge of -1 and metals in the same family often have a +2 oxidation state to achieve a stable compound. This interaction is part of an oxidation-reduction or redox reaction where metals lose electrons that are gained by bromine, leading to halide compounds with a consistent stoichiometry.

Step-by-step explanation:

The reason why metals in the same family react with bromine at a ratio of two bromines for every one metal is due to their similar chemical properties and the need to achieve a stable electron configuration. When bromine reacts with metals to form halide compounds, it does so with an oxidation state of -1 for each bromine atom. This is because bromine is a halogen and halogens form anions with a charge of -1.

Since two bromine atoms will have a combined oxidation charge of -2, the metal they react with must have a cation with a +2 oxidation state to balance the charge and form a neutral compound. This process, where the metal loses electrons and bromine gains, is known as an oxidation-reduction or redox reaction. Each metal atom loses two electrons (one to each bromine atom), which are gained by the bromine atoms, creating a stable, neutral compound.

For example, when sodium reacts with bromine, each sodium atom loses one electron to form a Na+ cation, and each bromine atom gains one electron to form two Br- anions. The same principle applies to other metals within that same family forming similar halide compounds.