Semester 2 Final Exam Review

What is the mass of 3.01 x 10^23 atoms of copper, given that the atomic mass of copper is approximately 63.5 g/mol?

• 10.5 grams

• 63.5 grams

• 5.29 grams

• 31.75 grams

What is the mass of 2 moles of chlorine (Cl2) gas?

• 284 grams

• 70.9 grams

• 35.45 grams

• 142 grams

What is the mass of 5 moles of propane (C3H8)?

• 180 g

• 44 g

• 100 g

• 220 g

What is the molar mass of NaCl?

• 22.99 g/mol

• 35.45 g/mol

• 58.44 g/mol

• 100.99 g/mol

How many molecules of carbon dioxide (CO2) weigh 4.4 x 10^-10 grams?

• 5.0 x 10^11 molecules

• 6.0 x 10^12 molecules

• 2.5 x 10^12 molecules

• 7.5 x 10^11 molecules

Water has the molecular formula of H₂O. How many atoms of hydrogen are there in 36 grams of water?

• 1.2 x 10²⁵ atoms of hydrogen

• 2.4 x 10²⁴ atoms of hydrogen

• 6.0 x 10²³ atoms of hydrogen

• 2.0 x 10²³ atoms of hydrogen

What is the mass percent of oxygen in water, H₂O?

• 92% oxygen

• 84% oxygen

• 80% oxygen

• 89% oxygen

Which of the following compounds has the largest molar mass?

• CO

• H₂O

• H₂O₂

• CO₂

What is the molar ratio of aluminum to iron (III) oxide in the balanced chemical equation for their reaction? 2 Al + Fe₂O₃ --> Al₂O₃ + 2 Fe

• 1:1

• 1:3

• 2:1

• 1:2

What is the mass in grams of 1.5 mol of Fe₂O₃?

• 240 grams

• 120 grams

• 160 grams

• 180 grams