Volume and pressure problems

1. One of the treatments for gangrene and "the bends," is hyperbaric oxygenation. This occurs in a chamber in which oxygen is used at higher-than-normal pressures. How many grams of oxygen are required to fill a 4.50 x 103 liter hyperbaric chamber at a pressure of 225 cm Hg and at 62° F? If the same quantity of oxygen was pumped back into a gas cylinder at a pressure of 200 atm. And at 75° F, What would the volume be?

2. The specific heat of fusion of silver is 25.0 calories per gram and the specific heat of silver is 0.25 Joules per gram per degree C. Calculate the energy required to melt 5.0 moles of silver if it stats as a solid at 25°C below its normal melting point and is heated to its normal melting point.

3. In the reaction of copper with concentrate nitric acid, the products are copper (II) nitrated, water and nitrogen monoxide, sometimes called nitric oxide. If 150 ml of nitric oxide were collected over mercury at 42°C and under a pressure of 74.5 cm of mercury, how many grams of copper had reacted?

4. The Law of DuLong and Petit states that the heat capacity per mole of many metals is approximately 6.0 calories per mole-degree C. Knowing that the specific heat capacity of three metals in Joules per gram-degree C. is 0.45 for Fe, 0.24 for Ag, and 0.13 for Au. Do these metals agree with the Law of DuLong and Petit? How do you know this? Using your understanding of bonding in metals, explain why this law appears to hold.

5. If all the nitric oxide from problem 10a was allowed to react with oxygen, a red-brown gas, nitrogen dioxide is formed. How many grams of nitrogen dioxide would be formed? How many oxygen molecules would be needed for this reaction?