AP Chemistry Molar Mass Calculation Questions and Tips

📚 Quick Study Guide

• ⚛️ Molar mass is the mass of one mole of a substance, usually expressed in grams per mole (g/mol).
• ➗ To calculate molar mass, sum the atomic masses of all the atoms in the chemical formula. Atomic masses are found on the periodic table.
• ➕ For example, the molar mass of water ($H_2O$) is calculated as: $2 \times$(atomic mass of H) + $1 \times$(atomic mass of O).
• 🔎 Remember to consider the subscripts in the chemical formula when calculating the total mass of each element.
• 💡 Polyatomic ions should be treated as a single unit when calculating molar mass.
• 📝 Use the correct units (g/mol) in your final answer.

🧪 Practice Quiz

1. Question 1: What is the molar mass of NaCl (Sodium Chloride)?
   1. A) 22.99 g/mol
   2. B) 35.45 g/mol
   3. C) 58.44 g/mol
   4. D) 116.88 g/mol
2. Question 2: What is the molar mass of $H_2SO_4$ (Sulfuric Acid)?
   1. A) 49.04 g/mol
   2. B) 98.08 g/mol
   3. C) 196.16 g/mol
   4. D) 65.04 g/mol
3. Question 3: What is the molar mass of $CuSO_4 \cdot 5H_2O$ (Copper(II) Sulfate Pentahydrate)?
   1. A) 159.61 g/mol
   2. B) 177.61 g/mol
   3. C) 249.68 g/mol
   4. D) 90.00 g/mol
4. Question 4: What is the molar mass of $Ca(OH)_2$ (Calcium Hydroxide)?
   1. A) 57.07 g/mol
   2. B) 74.09 g/mol
   3. C) 58.04 g/mol
   4. D) 41.05 g/mol
5. Question 5: What is the molar mass of $KMnO_4$ (Potassium Permanganate)?
   1. A) 110.94 g/mol
   2. B) 142.04 g/mol
   3. C) 158.03 g/mol
   4. D) 39.10 g/mol
6. Question 6: What is the molar mass of $C_6H_{12}O_6$ (Glucose)?
   1. A) 120.00 g/mol
   2. B) 180.16 g/mol
   3. C) 90.08 g/mol
   4. D) 24.00 g/mol
7. Question 7: What is the molar mass of $NH_4Cl$ (Ammonium Chloride)?
   1. A) 35.50 g/mol
   2. B) 19.00 g/mol
   3. C) 53.49 g/mol
   4. D) 14.01 g/mol