What is the molar mass of MgSO_4?

• A. 136.37 g/mol
• B. 96.21 g/mol
• C. 120.37 g/mol
• D. 142.32 g/mol

Answer: (A)

Verified step by step guidance

1. Identify the chemical formula of the compound: MgSO_4, which consists of magnesium (Mg), sulfur (S), and oxygen (O).
2. Find the atomic masses of each element from the periodic table: magnesium (Mg), sulfur (S), and oxygen (O).
3. Calculate the total mass contributed by each element by multiplying the atomic mass by the number of atoms in the formula: for Mg (1 atom), for S (1 atom), and for O (4 atoms).
4. Sum the masses of all elements to find the molar mass of MgSO_4 using the formula: \(\text{Molar mass} = (1 \times M_{Mg}) + (1 \times M_{S}) + (4 \times M_{O})\).
5. Express the final molar mass in units of grams per mole (g/mol).