Molar Mass Calculation Formula and Examples

📚 Quick Study Guide

• ⚛️ Molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol).
• 🔎 To calculate molar mass, use the periodic table to find the atomic masses of each element in the chemical formula.
• ➕ Multiply each element's atomic mass by the number of atoms of that element in the formula, then add these values together.
• 📝 The formula is: Molar Mass = $\sum$ (Atomic Mass of Element $\times$ Number of Atoms of Element)
• 💡 Units are crucial! Always include 'g/mol' in your answer.
• ⚖️ For example, to find the molar mass of water ($H_2O$):
  Molar Mass ($H_2O$) = (2 $\times$ Atomic Mass of H) + (1 $\times$ Atomic Mass of O)
  Molar Mass ($H_2O$) = (2 $\times$ 1.01 g/mol) + (1 $\times$ 16.00 g/mol) = 18.02 g/mol

🧪 Practice Quiz

1. What are the correct units for molar mass?
   1. grams (g)
   2. moles (mol)
   3. grams per mole (g/mol)
   4. moles per gram (mol/g)
2. What is the molar mass of sodium chloride (NaCl)? (Na = 22.99 g/mol, Cl = 35.45 g/mol)
   1. 57.44 g/mol
   2. 12.46 g/mol
   3. 58.44 g/mol
   4. 56.00 g/mol
3. What is the molar mass of water ($H_2O$)? (H = 1.01 g/mol, O = 16.00 g/mol)
   1. 17.01 g/mol
   2. 18.02 g/mol
   3. 19.00 g/mol
   4. 16.00 g/mol
4. Calculate the molar mass of carbon dioxide ($CO_2$). (C = 12.01 g/mol, O = 16.00 g/mol)
   1. 28.01 g/mol
   2. 44.01 g/mol
   3. 32.00 g/mol
   4. 12.01 g/mol
5. What is the molar mass of glucose ($C_6H_{12}O_6$)? (C = 12.01 g/mol, H = 1.01 g/mol, O = 16.00 g/mol)
   1. 90.00 g/mol
   2. 180.18 g/mol
   3. 120.00 g/mol
   4. 200.00 g/mol
6. What is the molar mass of sulfuric acid ($H_2SO_4$)? (H = 1.01 g/mol, S = 32.07 g/mol, O = 16.00 g/mol)
   1. 98.08 g/mol
   2. 49.04 g/mol
   3. 65.00 g/mol
   4. 32.07 g/mol
7. Find the molar mass of methane ($CH_4$). (C = 12.01 g/mol, H = 1.01 g/mol)
   1. 13.02 g/mol
   2. 15.00 g/mol
   3. 16.05 g/mol
   4. 17.03 g/mol