What is the formula for barium fluoride?

A. [tex]\( \text{Ba}_2\text{F} \)[/tex]

B. [tex]\( \text{Ba}_2\text{F}_2 \)[/tex]

C. [tex]\( \text{BaF} \)[/tex]

D. [tex]\( \text{BaF}_2 \)[/tex]



Answer :

To determine the formula for barium fluoride, we first need to understand the chemical symbols and charges of the ions involved.

1. Barium (Ba) Ion:
- Barium is an alkaline earth metal and typically forms a +2 charge when it becomes an ion. Therefore, the barium ion is denoted as [tex]\( \text{Ba}^{2+} \)[/tex].

2. Fluoride (F) Ion:
- Fluorine is a halogen and typically forms a -1 charge when it becomes an ion. Therefore, the fluoride ion is denoted as [tex]\( \text{F}^{-} \)[/tex].

To form a neutral compound, the total positive charge must balance the total negative charge. Given that a barium ion has a charge of +2 and a fluoride ion has a charge of -1, we need two fluoride ions to balance the charge of one barium ion:

[tex]\[ \text{Ba}^{2+} + 2\text{F}^{-} \][/tex]

This results in the chemical formula:

[tex]\[ \text{BaF}_2 \][/tex]

Therefore, the formula for barium fluoride is [tex]\( \text{BaF}_2 \)[/tex].

Let's identify the correct choice from the options provided:
A. [tex]\( \text{Ba}_2\text{F} \)[/tex]
B. [tex]\( \text{Ba}_2\text{F}_2 \)[/tex]
C. [tex]\( \text{BaF} \)[/tex]
D. [tex]\( \text{BaF}_2 \)[/tex]

The correct answer is:
D. [tex]\( \text{BaF}_2 \)[/tex]