UOP CMH109 week 5 exercises

University of Phoenix Material

Week 5 Exercises

Preparewritten answers to the following exercises:

1. Adapted from Exercise 36 in Ch. 11 of Introductory Chemistry:

A marine biologist may need to dive deep underwater for her research. To do so, she may want to know how to do calculations related to pressure and volume changes that occur, depending on the depth of the dive. Suppose she inhales air at a depth of 60 meters and at a pressure of 6 atm. Holding her breath, the marine biologist then ascends to a depth of 10 meters (where the pressure is now 2 atm). What volume would the air in her lungs expand to?

2. Environmental health and safety departments employ many environmental scientists to monitor and regulate business practices. Imagine that you work for the Environmental Protection Agency (EPA) to ensure that gas canisters are correctly pressurized.

You locate a canister that contains 0.72 moles of helium. However, the container is authorized by the manufacturer and by the EPA to hold no more than 20 liters (L) of gas. A typical 0.5 moles of helium gas occupies 13.0 L. Assume standard (STP) conditions.

a. Does the container containing 0.72 moles of helium follow EPA regulations?

b. Explain by determining the volume that 0.72 moles of helium gas would occupy if not pressurized.

3. Imagine that you are an organic chemist who is looking for a substance that will be miscible in water, yet contain carbon. You come across two compounds: CH3CH2CH2CH2CH3 and CH2OH. Which one is miscible in water and why?