UCCS PES/ENSC 2500 Questions & Problems
updated: Tuesday, January 26, 2021 15:02
please handwrite your answers, & show your work... thankx
chapter 1. ENERGY BASICS pg. 27-28
problems: 1.1, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8
due: monday, february 01, 2021
chapter 2. Past, Present, & Future World Energy Use
problems pg. 67 & 68
2.2, 2.3, & 2.5
due: TBD
Chapter 3. Fossil Fuel Resources and Use
problems 3.1, & 3.4 pg. 110
due: TBD
Problem 3.1 Write down the chemical formulae for the combustion of the alkanes in Table 3.2 with n = 2 to n = 8.
use columns to: Determine the mass of CO2 produced per megajoule of energy.
hint/catnip... The molecular mass (M) of CO2 (44 g/mol) can be used to determine the relative mass of CO2 produced per unit mass of alkane.
The heat of combustion is given in Table 3.2 and the amount of CO2 per MJ heat is found.
n =
R = (moles CO2) / (moles alkane)
M (alkane)
R ظ¤£ù 44/ M = (kg CO2) / (kg alkane)
heat of combustion MJ / kg
kg( CO2) / MJ-----------------------------------------------------------------------------------------------------------
Problem 3.4 Assume that all of the United States' annual electricity requirement of: 3 ظ¤£ù 10^12 kWh is produced by coal-fired generating stations operating at a net overall efficiency of 40%.
(a) How many tonnes of coal are burned per second? (Assume the coal is all bituminous)The total coal energy needed is:
Averaged over the year, this is a power output of:
As the energy content of bituminous coal is: 3.1 x 10^4 MJ/t from the Appendix V, the number of tonnes per second is:
(b) Assuming that coal is 100% carbon, how many tonnes of CO2 will be produced each year?for the combustion process: C + O2 into CO2
then 1 mole of C produces 1 mole CO2 or
12g (C) into 44g (CO2)
so 1 t of C produces:
Chapter 4. due: TBD
Environmental Consequences of Fossil Fuel Use.
4-1 Pluto has no atmosphere and has an average orbital diameter that is: 39.2 times that of the earth.
The mean surface temperature is: 37 K. Estimate the albedo of Pluto
4.3 A typical gasoline-powered vehicle requires about 3.7 MJ of primary energy (i.e., energy content of the gasoline) to travel 1 km.
How many kilograms of: CO2 are produced annually by a vehicle that is driven: 40,000 km per year?
4-9 (a) The orbit of Venus is at an average distance of 0.723 astronomical units from the sun. Given an albedo of 0.9, calculate the mean surface temperature if Venus has no atmosphere.
(b) Locate information about the actual surface temperature of Venus and discuss the relevance of your answer to part (a).
4.11 The earth╪╕┬╪تs moon has no atmosphere and has an albedo of 0.136. Calculate the total power radiated (in watts) from the moon╪╕┬╪تs surface.
4-19 The total mass of the atmosphere per unit area is equal to the atmospheric pressure at the surface of the earth divided by the gravitational acceleration. This follows from Newton╪╕┬╪تs law F = ma.
Assume that all carbon in the atmosphere is in the form of CO2 and that the current concentration (in ppm per volume) is 400 ppm. What is the total mass of carbon in the atmosphere?
TEST 1
due: TBD
