What is the molar mass of NaCl? (H = 1, C = 12, N = 14, O = 16, Na = 23, Mg = 24, Al = 27, S = 32, Cl = 35.5, K = 39, Ca = 40, Mn = 55, Fe = 56)
Answer and explanation
Correct answer: C. 58.5 g/mol
- Step 1: Add the atomic masses of all the atoms in the formula. Step 2. NaCl: 23 + 35.5 = 58.5 g/mol. Answer: 58.5 g/mol. Why not the others: 180 g/mol is what you get if you use the molar mass of C₆H₁₂O₆. 111 g/mol is what you get if you use the molar mass of CaCl₂. 98 g/mol is what you get if you use the molar mass of H₂SO₄.
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