To determine the molar mass of barium bromide ([tex]$BaBr_2$[/tex]), we need to sum the atomic masses of all the atoms present in the compound. [tex]$BaBr_2$[/tex] consists of one barium (Ba) atom and two bromine (Br) atoms.
1. Identify the atomic masses:
- The atomic mass of barium (Ba) is 137.33 g/mol.
- The atomic mass of bromine (Br) is 79.90 g/mol.
2. Calculate the molar mass of [tex]$BaBr_2$[/tex]:
- Since there are two bromine atoms in [tex]$BaBr_2$[/tex], we need to multiply the atomic mass of bromine by 2.
[tex]\[
\text{Total mass of bromine atoms} = 2 \times 79.90 \text{ g/mol} = 159.80 \text{ g/mol}
\][/tex]
- Now, add the mass of one barium atom to the total mass of bromine atoms to get the molar mass of [tex]$BaBr_2$[/tex].
[tex]\[
\text{Molar mass of } BaBr_2 = 137.33 \text{ g/mol} + 159.80 \text{ g/mol} = 297.13 \text{ g/mol}
\][/tex]
Based on this detailed calculation, the correct answer is:
B. [tex]$297.1 \text{ g/mol}$[/tex]
