Exam 2 - CHM 211

Which of the following statements regarding gas diffusion is correct?

A real gas behaves ideally at high temperatures and low pressures.

What is the total pressure in a container with partial pressures of 0.39 atm and 0.45 atm after adding 8.0 g of CO2?

The decomposition of potassium chlorate produces ______ as one of the products.

Match the following molecules with their properties:

Which orbitals on bromine atoms overlap in the formation of the bond in Br2?

The O2 molecule has no unpaired electrons.

How many liters of NH3 will be produced from the reaction of 5.00 L of N2 gas at 1.0 atm and 273 K?

An ideal gas differs from a real gas in that the molecules of an ideal gas have no ______ for one another.

Which type of molecular orbital describes a buildup of electron density along the axis connecting two atomic nuclei?

What molecular geometry is expected for a molecule with the formula AB4?

The total pressure of a mixture of gases equals the sum of the partial pressures exerted by each gas in the mixture.

Match the following concepts with their descriptions:

Exam 2 - CHM 211

Constants: R = 0.0821 L-atm/mol-K

Part I - Multiple Choice

Question 1: Br₂ bond formation involves overlap of bromine 4p orbitals.
Question 2: A σ molecular orbital describes electron density buildup along the axis connecting atomic nuclei.
Question 3: O₂ has 2 unpaired electrons and bond order of 2.
Question 4: An unknown gas that effuses 1.25 times faster than CO₂ could be H₂.
Question 5: The reaction of 5.00 L N₂ with excess H₂ produces 10.0 L NH₃ at specified conditions.
Question 6: An ideal gas has no intermolecular attractions, no molecular volume, and zero molecular weight.

Part II - Discussion Questions

Question 1: Molecules with 4 electron pairs around a central atom can exhibit sp³ hybridization and tetrahedral geometry. Double bonds are possible. Molecular polarity depends on the molecule's shape and bond polarities.
Question 2: Possible molecular geometries for AB₄ include tetrahedral. If there are 3 electron pairs around the central atom: possible geometries include trigonal planar and bent.
Question 3: Gases form homogeneous mixtures, total gas pressure is the sum of partial pressures, gas molecules have the same kinetic energy at the same temperature, diffusion rate is inversely related to molecular mass. At high temperatures and pressures, real gases deviate from ideal gas behavior.

Additional Questions

Question 4: Calculating the total pressure of a gas mixture after additional gas addition requires using partial pressures and the ideal gas law.
Question 5: Determine the KClO₃ mass needed to produce 5.0 L of O₂ at standard temperature and pressure (STP).
Question 6: Draw Lewis structures, determine molecular geometry (e.g., SO₂, XeF₅⁺), and identify molecular polarity for SO₂ and XeF₅⁺.
Question 7: This question deals with pain relief medication (Ibuprofen). a) Calculate the number of π (pi) bonds in the molecule. b) Estimate bond angles. c) Identify hybrid orbitals about central atoms. d) Determine molecular geometries.

This quiz covers topics in CHM 211, focusing on molecular bonding, orbital hybridization, and gas laws. Participate to test your knowledge on molecular geometry and gas effusion principles, along with several multiple-choice questions and discussion prompts related to chemical bonding concepts.