To determine the correct chemical formula of magnesium bromide, follow these steps:
1. Identify the ions involved:
- Magnesium forms cations with a charge of [tex]\( +2 \)[/tex]. Its symbol is [tex]\( Mg^{2+} \)[/tex].
- Bromine forms anions with a charge of [tex]\( -1 \)[/tex]. Its symbol is [tex]\( Br^{-} \)[/tex].
2. Balance the charges:
- To create a neutral compound, the total positive charge must balance the total negative charge.
3. Using the charges to combine the ions:
- Since a magnesium ion [tex]\( Mg^{2+} \)[/tex] has a [tex]\( +2 \)[/tex] charge and a bromine ion [tex]\( Br^{-} \)[/tex] has a [tex]\( -1 \)[/tex] charge, you need two bromine ions to balance one magnesium ion.
4. Write the chemical formula:
- Combining one [tex]\( Mg^{2+} \)[/tex] ion with two [tex]\( Br^{-} \)[/tex] ions gives the formula [tex]\( MgBr_2 \)[/tex].
Thus, the correct chemical formula of magnesium bromide is:
A. [tex]$MgBr_2$[/tex]