EEML 3100 - Thermodynamics

EML 3100 - Homework 3 Due 10/9/23 All problems use the ideal gas model: where needed, break the problems down into the steps demonstrated in class. Define the substance and the state of the system. Problem 1 (10pt) A spherical helium balloon with 12m diameter is at a temperature T=15 C, P=100kPa. a) How much helium does it contain? b) How much lift does the balloon generate if it is surrounded by air at the same temperature and pressure? Problem 2 (10pt) A 1m' rigid tank is filled with a gas at room temperature (22 C) and pressure (101kPa). How much mass is there if the gas is a) air b) neon c) propane ? Problem 3 (10pt) A 1m' tank has propane gas at 100kPa, 300K. It is connected by a valve to a second tank of volume 0.5m' with propane at 250kPa, 400K. The valve is now opened and the two tanks settle to a uniform state at a temperature of 325K. What is the final pressure? Problem 4 (10pt) A rigid tank of 2m' contains pure nitrogen gas at 1000kPa and 400K. A mass of 1.8kg is removed from the tank. The final temperature is 375K. What is the final pressure? Problem 5 (15pt) A glass is cleaned in hot water and reaches a temperature of 50 C. The glass is placed on a table bottom up. The room temperature air trapped in the glass heats up to 46 C, and some of the air escapes, so that the resulting pressure in the glass is 2kPa higher than the ambient pressure of 100kPa. The weight of the glass now seals the volume. The glass and air are let to cool to 20 C. What is the pressure inside the glass