Final answer:
Around 0.72% of naturally occurring uranium is the fissionable isotope U-235. After processing and enriching, about 27,300 tons of U-235 can be used from Canada's reserves, providing substantial energy but only a fraction compared to fossil fuel reserves.
Step-by-step explanation:
The main answer to the question of how much of Canadian Uranium ore is useful fissionable product is based on the composition and enrichment process of uranium. Naturally occurring uranium contains approximately 0.72% uranium-235 (U-235), which is the isotope capable of sustaining a nuclear fission reaction. However, for use in nuclear reactors, this concentration needs to be increased, usually via an enrichment process to about 3% to 5%. Considering that not all the mined U-235 can be extracted and burned in reactors — optimistically, only about half — a significant amount of raw uranium ore must be processed to obtain a relatively small quantity of fissionable material.For example, if we take an optimistic scenario where half of the 0.72% of U-235 in the 7.6 million tons of proven uranium reserves is used, it equates to approximately 27,300 tons of usable U-235. With each gram of U-235 releasing about 17 million kcal of energy, this amounts to a total energy output of approximately 2×10²¹ Joules. However, when comparing to fossil fuel reserves, it provides only 20% as much energy as proven oil reserves and about 5% of the total fossil fuel supply. If we relied solely on uranium for energy, utilizing it at the rate of 18 TW, these reserves would last under 4 years, questioning the sustainability of uranium as a long-term energy source.In conclusion, while uranium is a significant source of energy, the usable portion of U-235 in uranium ore is limited due to its low natural occurrence and the inefficiencies in the extraction and enrichment process. This highlights the need for efficient use of the resource and consideration of alternative energy sources for the future.