The question provides a table with the atomic mass of a few elements (beryllium, copper, cadmium, calcium and iodine) and requires us to calculate the molar mass of the salts BeI2, CuI2, CdI2 and CaI2.
The molar mass of a compound is calculated considering the atomic mass of the elements that compose the molecule and the amount of atoms of each of these elements. Considering the hypothetical compound AX2, its molar mass would be calculated as:
[tex]\text{molar mass of AX}_2=(1\times atomic\text{ mass of A) + (2}\times atomic\text{ mass of X)}[/tex]Since the question provided the atomic mass of the elements, we can calculate the molar mass of the salts given in a similar way as the equation above for AX2.
- For BeI2:
[tex]\begin{gathered} \text{molar mass BeI}_2=(1\times atomic\text{ mass Be) + (2}\times atomic\text{ mass I)} \\ \text{molar mass BeI}_2=(1\times9.012g/\text{mol)}+(2\times126.90g/\text{mol) = 262.}81g/\text{mol} \end{gathered}[/tex]The molar mass of BeI2 is 262.81 g/mol.
- For CuI2:
[tex]\begin{gathered} \text{molar mass CuI}_2=(1\times atomic\text{ mass Cu) + (2}\times atomic\text{ mass I)} \\ \text{molar mass CuI}_2=(1\times63.55g/\text{mol)}+(2\times126.90g/\text{mol) = 317.35}g/\text{mol} \end{gathered}[/tex]The molar mass of CuI2 is 317.35 g/mol.
- For CdI2:
[tex]\begin{gathered} \text{molar mass CdI}_2=(1\times atomic\text{ mass Cd) + (2}\times atomic\text{ mass I)} \\ \text{molar mass CdI}_2=(1\times112.41g/\text{mol)}+(2\times126.90g/\text{mol) = 366.21}g/\text{mol} \end{gathered}[/tex]The molar mass of CdI2 is 366.21 g/mol.
- For CaI2:
[tex]\begin{gathered} \text{molar mass CaI}_2=(1\times atomic\text{ mass Ca) + (2}\times atomic\text{ mass I)} \\ \text{molar mass CaI}_2=(1\times40.08g/\text{mol)}+(2\times126.90g/\text{mol) = 293.88}g/\text{mol} \end{gathered}[/tex]The molar mass o CaI2 is 293.88 g/mol.
