Calculate the molar mass of magnesium chloride, MgCl 2 125.9 g 59.8 g 95.28 70.0 g 24.38
The correct answer and explanation is :
To calculate the molar mass of magnesium chloride (MgCl₂), we need to sum the molar masses of the constituent elements in the compound. Magnesium chloride consists of one magnesium (Mg) atom and two chlorine (Cl) atoms.
Step 1: Determine the atomic masses of magnesium and chlorine
- Magnesium (Mg): The atomic mass of magnesium is approximately 24.38 g/mol.
- Chlorine (Cl): The atomic mass of chlorine is approximately 35.45 g/mol.
Step 2: Molar mass of MgCl₂
Magnesium chloride contains one magnesium atom and two chlorine atoms. Therefore, the molar mass of MgCl₂ can be calculated as follows:
[
\text{Molar mass of MgCl₂} = \text{(1 × atomic mass of Mg)} + \text{(2 × atomic mass of Cl)}
]
[
\text{Molar mass of MgCl₂} = (1 \times 24.38\ \text{g/mol}) + (2 \times 35.45\ \text{g/mol})
]
[
\text{Molar mass of MgCl₂} = 24.38\ \text{g/mol} + 70.90\ \text{g/mol}
]
[
\text{Molar mass of MgCl₂} = 95.28\ \text{g/mol}
]
Step 3: Conclusion
The molar mass of magnesium chloride (MgCl₂) is 95.28 g/mol.
Explanation
The molar mass of a compound is the sum of the atomic masses of all the elements present in the formula, each multiplied by the number of atoms of that element in the compound. In this case, the compound MgCl₂ has one magnesium atom and two chlorine atoms. Using the atomic masses of magnesium (24.38 g/mol) and chlorine (35.45 g/mol), we add the appropriate amounts to find that the molar mass of MgCl₂ is 95.28 g/mol. This value is essential in various applications such as stoichiometric calculations, determining the amount of substance in a given sample, and understanding the chemical properties of the compound.