PSC20
Assignment (Energy & Astronauts)
Whenever organic matter is decomposed under oxygen-free (anaerobic) conditions, methane is
one of the products. Thus, enormous deposits of natural gas, which is almost entirely methane,
serve as a major source of fuel for home and industry.
05 Jun 2023
a) Known sources of natural gas can produce 5600 EJ of energy (1 EJ-10¹8 J). Current total
global energy usage is 4.0 x 102 EJ per year. Find the mass in (in kg) of known sources of
natural gas (AHrn for the combustion of CH4-802 kJ/mol).
AH-802kJ/mol
16j=1018 = 10 x 10¹8 Kj
1k of energy
$600-5600/802
is released by 1/802 mol of CHY
mol CH 4 = 5600 × 10^18× 10^-3kj
= 5600
16.982 x 1015 mol = 161 802 mol = 6.982×10^15 mol C
b) For how many years could these sources supply the world's total energy needs?
c) What volume (in ft³) of natural gas, measured at STP, is required to heat 1.00 qt of water
from 25.0°C to 100.0°C (d of H₂O = 1.00 g/mL; d of CH4 = 0.72 g/L)?
d) The fission of 1 mol of uranium (about 4 x 10^-4 ft³) in a nuclear reactor produces
2 x 10^13 J. What volume (in ft3) of natural gas would produce the same amount of energy?