Question

the relative formula mass for MgCl2

Answer 1

To calculate the relative formula mass (molar mass) of magnesium chloride (MgCl₂), you need to sum the atomic masses of its constituent elements:

- Magnesium (Mg): Approximately 24.31 g/mol
- Chlorine (Cl): Approximately 35.45 g/mol

Since there are two chlorine atoms in magnesium chloride, you multiply the atomic mass of chlorine by 2:

\[
\text{Relative formula mass of MgCl}_2 = \text{(Atomic mass of Mg)} + 2 \times \text{(Atomic mass of Cl)}
\]

\[
= 24.31 \, \text{g/mol} + 2 \times 35.45 \, \text{g/mol}
\]

\[
= 24.31 \, \text{g/mol} + 70.90 \, \text{g/mol}
\]

\[
= 95.21 \, \text{g/mol}
\]

Therefore, the relative formula mass of MgCl₂ is approximately **95.21 g/mol**.