Molar Mass Mastery: Double-Check Challenge

A scientist is calculating the molar mass of sodium chloride (NaCl). What is the molar mass of NaCl?

• 35.45 g/mol

• 58.44 g/mol

• 22.99 g/mol

• 60.00 g/mol

Answer explanation

The molar mass of sodium (Na) is 22.99 g/mol and chlorine (Cl) is 35.45 g/mol. Adding these gives NaCl a total molar mass of 58.44 g/mol, making the correct answer 58.44 g/mol.

Dr. Smith is double-checking his work on the molar mass of water (H₂O). Calculate the molar mass of water.

• 16.00 g/mol

• 18.02 g/mol

• 20.00 g/mol

• 2.02 g/mol

Answer explanation

The molar mass of water (H2O) is calculated by adding the molar masses of its components: 2 hydrogen (1.01 g/mol each) and 1 oxygen (16.00 g/mol). Thus, (2 x 1.01) + 16.00 = 18.02 g/mol, making the correct answer 18.02 g/mol.

A chemist is tasked with finding the molar mass of calcium carbonate (CaCO₃). What is the correct molar mass?

• 100.09 g/mol

• 40.08 g/mol

• 44.01 g/mol

• 84.09 g/mol

Answer explanation

To find the molar mass of CaCO3, sum the atomic masses: Ca (40.08 g/mol) + C (12.01 g/mol) + 3 O (3 x 16.00 g/mol = 48.00 g/mol). Total: 40.08 + 12.01 + 48.00 = 100.09 g/mol, making the correct answer 100.09 g/mol.

Dr. Lee is working on a project that involves the molar mass of glucose (C₆H₁₂O₆). Calculate the molar mass of glucose to the nearest whole number, do not include units in your answer.

Mathematical Equivalence

ON

A scientist is reviewing the molar mass calculation of sulfuric acid (H₂SO₄). What is the molar mass of sulfuric acid?

Match each of the elements in H₂SO₄ with the correct molar mass

• Oxygen (O)

• 16.00 g/mol

• Sulfur (S)

• 1.01 g/mol

• Hydrogen (H)

• 32.06 g/mol

Dr. Patel is analyzing the molar mass of ammonium nitrate (NH₄NO₃) for a fertilizer study.

Match each of the elements in NH₄NO₃ with the correct count of its atoms

• Hydrogen

• 2 atoms

• Oxygen

• 3 atoms

• Nitrogen

• 4 atoms

A researcher is tasked with determining the molar mass of magnesium sulfate (MgSO₄). What is the molar mass of magnesium sulfate?

• 120.37 g/mol

• 150.37 g/mol

• 100.37 g/mol

• 140.37 g/mol

Answer explanation

To find the molar mass of magnesium sulfate (MgSO4), add the atomic masses: Mg (24.31 g/mol) + S (32.07 g/mol) + 4 x O (16.00 g/mol) = 120.37 g/mol. Thus, the correct answer is 120.37 g/mol.

Dr. Kim is verifying the molar mass of acetic acid (CH₃COOH) for a lab experiment. Calculate the molar mass of acetic acid to the nearest whole number, do not include units in your answre.

Mathematical Equivalence

ON

A scientist is tasked with calculating the molar mass of potassium permanganate (KMnO₄). What is the molar mass of potassium permanganate?

• 158.04 g/mol

• 128.04 g/mol

• 148.04 g/mol

• 168.04 g/mol

Answer explanation

To calculate the molar mass of KMnO4, sum the atomic masses: K (39.10 g/mol) + Mn (54.94 g/mol) + 4 x O (16.00 g/mol) = 39.10 + 54.94 + 64.00 = 158.04 g/mol. Thus, the correct answer is 158.04 g/mol.

Dr. Johnson is working on a project that involves the molar mass of aluminum sulfate (Al₂(SO₄)₃). Calculate the molar mass of aluminum sulfate.

How many oxygen atoms are in Al₂(SO₄)₃?

Mathematical Equivalence

ON